Document:

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                                                                   EXHIBIT 10.18

                       AMENDMENT NO. 6 TO CREDIT AGREEMENT

         AMENDMENT dated as of June 8, 1999 to the Amended and Restated Credit
Agreement dated as of June 8, 1999 (the "CREDIT AGREEMENT") among HALLWOOD
ENERGY CORPORATION, HALLWOOD ENERGY PARTNERS, L.P. and HALLWOOD CONSOLIDATED
RESOURCES CORPORATION (collectively, the "BORROWERS"), the BANKS party thereto
(the "BANKS"), FIRST UNION NATIONAL BANK, as Collateral Agent and MORGAN
GUARANTY TRUST COMPANY OF NEW YORK, as Agent (the "AGENT").

                                   WITNESSETH:

         WHEREAS, the parties hereto desire to amend the Credit Agreement as set
forth herein;

         NOW, THEREFORE, the parties hereto agree as follows:

         SECTION 1. Defined Terms; References. Unless otherwise specifically
defined herein, each term used herein which is defined in the Credit Agreement
has the meaning assigned to such term in the Credit Agreement. Each reference to
"hereof", "hereunder", "herein" and "hereby" and each other similar reference
and each reference to "this Agreement" and each other similar reference
contained in the Credit Agreement shall, after this Amendment becomes effective,
refer to the Credit Agreement as amended hereby.

         SECTION 2. Amendment of the Distributions Covenant. Clause (b) of the
first sentence of Section 4.21 of the Credit Agreement is amended to read in its
entirety as follows: "(b) if the aggregate Debt of HEC and its Subsidiaries
(other than the Subordinated Notes) exceeds, or would immediately after such
Distribution exceed, 100% of the Debt Limit;".

         SECTION 3. Representations of Borrowers. The Borrowers represent and
warrant that (i) the representations and warranties of the Borrowers set forth
in Article 3 of the Credit Agreement are true on and as of the date hereof and
(ii) no Default has occurred and is continuing.

         SECTION 4. Governing Law. This Amendment shall be governed by and
construed in accordance with the laws of the State of New York.

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         SECTION 5. Counterparts. This Amendment may be signed in any number of
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.

         SECTION 6. Effectiveness. This Amendment shall become effective as of
the date hereof on the date on which the Agent shall have received from the
Borrowers and the Required Banks a counterpart hereof signed by such party or
facsimile or other written confirmation (in form satisfactory to the Agent) that
such party has signed a counterpart hereof.

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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed as of the date first above written.

                                            HALLWOOD ENERGY CORPORATION

                                            By: /s/ Bill Baumgartner
                                                --------------------------------
                                                Title: Vice President

                                            HALLWOOD CONSOLIDATED
                                                RESOURCES CORPORATION

                                            By: /s/ Bill Baumgartner
                                                --------------------------------
                                                Title: Vice President

                                            HALLWOOD ENERGY PARTNERS, L.P.

                                            By: HEC Acquisition Corp., its
                                                General Partner

                                            By: /s/ Bill Baumgartner
                                                --------------------------------
                                                Title: Vice President

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                                            MORGAN GUARANTY TRUST
                                                COMPANY OF NEW YORK

                                            By: /s/ John Kowalczuk
                                                --------------------------------
                                                Title:  Vice President

                                            FIRST UNION NATIONAL BANK

                                            By: /s/ Robert R. Wetteroff
                                                --------------------------------
                                                Title: Senior Vice President

                                            WELLS FARGO BANK TEXAS, N.A.

                                            By: /s/ Todd Stornetta
                                                --------------------------------
                                                Title: Vice President

                                       4
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         Acknowledged by:

                                  HALLWOOD LA PLATA, LLC
                                  LA PLATA ASSOCIATES, LLC

                                  By: HALLWOOD PETROLEUM, INC.

                                  By: /s/ Bill Baungartner
                                     -------------------------------------------
                                      Title: Vice President

                                  The Manager of Hallwood La Plata LLC and La
                                     Plata Associates LLC

                                  CONCISE OIL AND GAS PARTNERSHIP
                                  EM NOMINEE PARTNERSHIP COMPANY
                                  MAY ENERGY PARTNERS OPERATING
                                            PARTNERSHIP LTD.

                                  By: HEC ACQUISITION CORP.

                                  By: /s/ Bill Baungartner
                                     -------------------------------------------
                                      Title: Vice President

                                  The General Partner of Concise Oil and Gas
                                  Partnership, EM Nominee Partnership Company,
                                  May Energy Partners Operating Partnership LTD.

                                  HALLWOOD CONSOLIDATED PARTNERS, L.P.

                                  By: HALLWOOD CONSOLIDATED
                                      RESOURCES CORPORATION

                                  By:  /s/ Bill Baungartner
                                     -------------------------------------------
                                       Title: Vice President

                                  The General partner of Hallwood Consolidated
                                        Partners, L.P.

                                        5<PAGE>   1

                                                                   EXHIBIT 10.1

                   SETTLEMENT AGREEMENT AND RELEASE OF CLAIMS

         THIS SETTLEMENT AGREEMENT AND RELEASE OF CLAIMS (the "Agreement") is
made and entered into this 19th day of April, 2001, by and between THE BOEING
COMPANY (acting through its division, BOEING COMMERCIAL AIRPLANES) ("Boeing")
and TITANIUM METALS CORPORATION ("TIMET"). Boeing and TIMET are collectively
referred to herein as the "Parties."

                                    RECITALS

         A. The Parties previously entered into that certain Purchase and Sale
Agreement (for titanium products) dated November 5, 1997 (the "Original
Agreement").

         B. Disputes have arisen between the Parties with respect to certain
matters under the Original Agreement.

         C. In connection with such disputes, on March 21, 2000 TIMET filed a
lawsuit in the District Court for the City and County of Denver, State of
Colorado entitled Titanium Metals Corporation v. The Boeing Company, 00CV1402
(the "Litigation"). The Parties enter into this Agreement to compromise a
disputed claim, and neither Party admits any liability.

         NOW, THEREFORE, in consideration of the execution and delivery of this
Agreement and of the mutual promises contained herein, the Parties agree to be
legally bound by all of the terms and conditions contained in this Agreement, as
follows:

                              TERMS AND CONDITIONS

         1. No later than the third business day following the date of execution
of this Agreement, Boeing will pay TIMET the sum of eighty-two million dollars
($82,000,000.00) , by wire transfer to an account designated by TIMET.

         2. Contemporaneously with the execution of this Agreement, each of the
Parties shall execute and deliver to the other Party: (a) the Amended and
Restated Purchase and Sale Agreement (for titanium products), originally dated
as of November 5, 1997, amended and restated effective as of April 19, 2001 in
the form last exchanged between the parties (the "Amended Agreement"), pursuant
to which Boeing will have the right but not the obligation to purchase titanium
products from TIMET, all on the terms and subject to the conditions set forth
therein, (b) the Inventory Purchase and Storage Agreement in the form last
exchanged between the parties (the "Buffer Agreement"), pursuant to which Boeing
will purchase certain titanium products from TIMET which TIMET will hold for
Boeing, on the terms and subject to the conditions set forth therein, and (c) a
side letter covering certain related matters (the "Side Letter").

         3. Upon satisfaction of the obligations set forth in Sections 1 and 2
above, the Parties shall execute the stipulation of dismissal (the "Dismissal")
attached hereto as Exhibit A to dismiss with prejudice all claims asserted
against one another in the Litigation, which Dismissal shall be filed by
attorneys for TIMET with the District Court for the City and County of Denver,
State of Colorado

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promptly following the execution thereof (but in any event, no later than two
business days thereafter). Each of the Parties shall bear its own costs,
expenses and attorneys' fees.

         4. Subject to the satisfaction by Boeing of all of the obligations set
forth in Sections 1, 2 and 3 above, TIMET, on behalf of itself and its present
and former directors, officers, subsidiaries, and any of their respective
predecessors, successors or assigns, jointly and severally, hereby voluntarily
releases and discharges Boeing from any and all liability, claims, demands,
injuries, promises, representations, conduct, losses, damages, costs, expenses,
judgments, attorneys' fees, actions or causes of action, of whatever kind or
nature accruing, in whole or in part, prior to the date of this Agreement which
TIMET had, now has, or may ever have against Boeing and which arose under or in
connection with the Original Agreement (collectively the "Claims"), whether such
Claims are known or unknown, suspected or unsuspected, matured or unmatured,
vested or contingent, direct or indirect, in law or in equity, including without
limitation, all claims that were made or could have been made by TIMET against
Boeing as part of the Litigation; provided, however, that TIMET does not
release, and the foregoing accordingly shall not apply, (i) to any obligations
of Boeing (or any other person) pursuant to any Order entered into prior to the
date of this Agreement pursuant to the terms of the Original Agreement, all of
which Orders shall remain unaffected by this Agreement and (ii) to any
obligations of Boeing under this Agreement, the Amended Agreement, the Buffer
Agreement, the Dismissal or the Side Letter.

         5. Subject to the satisfaction by TIMET of all of the obligations set
forth in Sections 1, 2 and 3 above, Boeing, on behalf of itself and its present
and former directors, officers, subsidiaries, and any of their respective
predecessors, successors or assigns, jointly and severally, hereby voluntarily
releases and discharges TIMET from any and all liability, claims, demands,
injuries, promises, representations, conduct, losses, damages, costs, expenses,
judgments, attorneys' fees, actions or causes of action, of whatever kind or
nature accruing, in whole or in part, prior to the date of this Agreement which
Boeing had, now has, or may ever have against TIMET and which arose under or in
connection with the Original Agreement (collectively the "Claims"), whether such
Claims are known or unknown, suspected or unsuspected, matured or unmatured,
vested or contingent, direct or indirect, in law or in equity, including without
limitation, all claims that were made or could have been made by Boeing against
TIMET as part of the Litigation; provided, however, that Boeing does not
release, and the foregoing accordingly shall not apply, (i) to any obligations
of TIMET (or any other person) pursuant to any Order entered into prior to the
date of this Agreement pursuant to the terms of the Original Agreement, all of
which Orders shall remain unaffected by this Agreement and (ii) to any
obligations of TIMET under this Agreement, the Amended Agreement, the Buffer
Agreement, the Dismissal or the Side Letter.

         6. Each of the Parties understands and acknowledges that by signing
this Agreement, it is forever giving up the right to sue or attempt to recover
money, damages or any other relief from the other Party for the matters from
which it is specifically releasing such other Party hereunder, that this
Agreement is in full accord and satisfaction of all such released matters, and
that the releases made herein shall constitute final and complete releases with
respect to all such released matters.

         7. No representations, covenants, warranties, or promises have been
made by the Parties other than those expressly contained herein or in the
documents referred to herein. This Agreement, the Amended Agreement, the Buffer
Agreement, the Dismissal and the Side Letter, taken together, represent the
complete and exclusive statement of the agreement between the Parties with
respect to the matters covered herein, and supersede all proposals or prior
agreements, oral or written, and all other communication between the Parties
relating to the subject matter herein. The Parties understand

                                       -2-
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and acknowledge that this Agreement is made without reliance upon any statement
or representation other than those contained herein and agree that this
Agreement shall not be subject to any claim of mistake of fact.

         8. Each Party represents and warrants to the other that it has not made
or purported to make any assignment or other disposition, in whole or in part,
of any claim(s) which were or are the subject of the Litigation, and that there
is no person, corporation, association or other entity which, through
assignment, subrogation, operation of law, or otherwise, has acquired any right
to pursue, bring legal action upon or recover on account of the claim of that
Party for the matters settled and released hereby. Each Party represents and
warrants to the other Party that the individual signing this Agreement on its
behalf is duly authorized to execute this Agreement and to bind such Party, and
each Party acknowledges that it has agreed to the terms of this Agreement
knowingly and voluntarily, after having had the opportunity to consult with
legal counsel.

            9. This Agreement (for the purpose of this Section 9 the term "this
Agreement" includes all documents and/or agreements referred to in the
Agreement) and the fact and terms of this Agreement and all communications
leading up to or relating to the terms of this Agreement are confidential and
shall not be disclosed by any Party or its agents or representatives to any
person (excluding the Parties' directors and employees having a need to know)
other than as disclosure is required by applicable law, regulation or court
order; provided, however, that either Party may make disclosure of this
Agreement to (a) any of its accountants, auditors, or lawyers having a need to
know such information, provided such person agrees not to disclose the
information to any other person or outside of such firm, except as disclosure is
required by applicable law, regulation or court order and (b) any of its bankers
or credit rating agencies having a need to know such information, provided
persons at such company agree in writing not to disclose the information to any
other person or outside of such company, except as disclosure is required by
applicable law, regulation or court order. The foregoing shall not apply to
matters already public other than by reason of a breach of this Section 9.
Notwithstanding the foregoing, either Party may disclose that the Litigation has
been settled. In addition, Boeing agrees that TIMET may issue the press release
(in the form last provided by TIMET to Boeing) announcing the settlement and may
discuss the terms of such settlement in investor calls only as such matters are
specifically stated in the press release.

         10. This Agreement may not be amended or waived, except by written
instrument signed by the Party against whose interests the enforcement of any
amendment or waiver is sought.

         11. This Agreement may be executed in multiple, identical counterparts,
each of which shall be deemed an original but all of which shall constitute one
and the same instrument.

         12. This Agreement shall be governed by and construed in accordance
with the substantive laws of the State of Washington, without regard to the
conflict of laws provisions thereof.

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         IN WITNESS WHEREOF, Titanium Metals Corporation and The Boeing Company,
intending to legally bind themselves, have executed this Settlement Agreement
and Release of Claims as of the date first hereinabove set forth.

                                    TITANIUM METALS CORPORATION

                                    By:    /s/ J. Landis Martin
                                           ------------------------
                                    Title: Chairman and CEO
                                           ------------------------

                                    THE BOEING COMPANY (ACTING THROUGH
                                    ITS DIVISION, BOEING COMMERCIAL AIRPLANES)

                                    By:    /s/ Mark Lough
                                           ------------------------
                                    Title: Counsel
                                           ------------------------

                                      -4-

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