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                                                                    EXHIBIT 4.12


                         CHEQUEMATE INTERNATIONAL, INC.
                                d/b/a C3D Digital
                         330 Washington Blvd. Suite 507
                         Marina del Rey, Ca. 90292-5146
                                 (310) 306-6666
                               (310) 305-1455 fax
Bill Massey, CEO
Cinema Internet Networks, Inc.
320-1333 Johnston Street
Vancouver, BC V6H 3R9

Re:   Exclusive Agent Agreement for the Canadian PPV Assets      August 3, 2000

Dear Bill:

This is an Exclusive Agent Agreement between our two companies, and we have
agreed that:

     1.   CinemaWorks (CWK) has the exclusive right to sell the Canadian PPV
          assets specified in the PPV Asset Purchase Agreement signed by the
          Parties on or about March 1, 2000.
     2.   Because CWK has title to the Canadian PPV assets, it is CWK's
          responsibility to provide clear title to the assets to the buyer.
     3.   The term of this Exclusive Agent Agreement is one year.
     4.   CWK shall retain all costs and stock proceeds from the sale of these
          assets, and the sale price and terms will be the sole responsibility
          and decision of CWK. If the proceeds from the sale are in the form of
          publicly traded stock, it shall be valued at the average market price
          for the previous five working days. If not publicly traded, Chequemate
          and CWK must agree on its value prior to the sale.

     5.   CWK will use its best efforts to maximize the sale price of the PPV
          assets on behalf of CWK and Chequemate.

Very truly yours,

  /s/ Alan Hunter
----------------------------
Alan Hunter
General Counsel
Chequemate International, Inc.

Cinema Internet Networks, Inc. agrees to the above provisions.

  /s/ William Massey                                 August 3, 2000
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William Massey, CEO                              Dated


Chequemate International Inc.                                    August 3, 2000
330 Washington Ste. 330
Marina Del Rey, Ca. 90292

Attn:  Michael Heil CEO
          cc:  Alan Hunter and Paul LaBarre


This letter is to confirm our phone conversation today between myself, Paul
LaBarre and Bill Massey. We have agreed on the following in order to close the
purchase of the CinemaWorks ("CWK") assets by Chequemate ("C-3D"). The following
amendments were agreed to by the parties. All dollars are US$ unless otherwise
noted.

     1.  a) The new agreed net purchase price of the PPV assets is $251,000. At
         this price, CWK still retains the Integra lease obligation until the
         lease is paid by CWK or assigned to a purchaser of the Canadian PPV
         assets.

         b) To purchase the PPV assets, Chequemate will immediately deliver to
         the escrow agent a certificate for 55,000 restricted shares and
         immediately file a registration statement (S-3) with respect to those
         shares to be released when shareholder approval is obtained by
         CinemaWorks.

         c) In addition, Chequemate will immediately place 40,000 restricted
         C-3D Shares (144 stock) in escrow with Paige Fraser. The holding period
         for these shares will begin on the date of this Agreement between the
         parties.

     2.  Cinema Works will immediately (within 1 working day of Paige Fraser
         receiving the Shares in #1 in escrow) call an extraordinary shareholder
         meeting to approve the disposition of the PPV assets, a fait accompli.
         This step is anticipated to be completed in approximately 30 days.

     3.  CWK and Chequemate will sign a separate "Exclusive Agent Agreement"
         allowing CinemaWorks exclusive right to sell the Canadian PPV assets
         for an amount solely determined by CinemaWorks. However, CWK will use
         its best efforts to maximize the sale price of the assets.

     4.  Title to the PPV assets in Canada will remain with CWK until such time
         as the assets are sold by CWK and title is transferred to a new buyer.
         All cash and/or stock proceeds from the purchase will be retained by
         CWK.

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     5.  Until, the PPV assets in Canada are sold or until the restricted Shares
         are released from escrow as per #7 below, Chequemate and its
         subsidiary, Hotel Movie Network (HMN), will provide monthly new movies
         and perform service calls for the Canadian hotel PPV systems in the
         same professional manner as they do for the USA-based PPV assets. At
         the same time, all monthly PPV movie revenues collected from the
         Canadian PPV assets will continue to be sent to CWK. CinamaWorks will
         also continue to invoice the Canadian PPV assets until the assets are
         sold or until the 144 Shares are saleable under Rule 144 and released
         from escrow as per #7 below.

     6.  CinemaWorks will continue to be liable for-and pay the Integra lease
         payment each month from revenues collected in #5. And, the balance of
         collected revenues will be sent to Chequemate on a quarterly basis
         until such time as the Canadian PPV assets are sold to another company.

     7.  a) If CWK for any reason is unable to sell the Canadian PPV assets,
         then the restricted stock will be transferred to CWK from escrow after
         one (1) year and the Shares become saleable under Rule 144.

              a)   However, simultaneous with those Shares being released from
                   escrow to CWK, CinemaWorks will assign free and clear title
                   of the Canadian PPV assets to Chequemate.

              b)   If there is money still owed on the Integra lease by CWK at
                   this time, then it will be CWK's sole obligation to pay the
                   remainder of the Integra lease.

     8.  CWK will see shareholder approval for the disposition of its PPV
         assets, with the understanding that the lease obligation to Scott
         Applegate must be removed from Bill Massey and CinemaWorks either
         directly by Applegate or by Chequemate after taking assignment of this
         obligation from Applegate. This may be accomplished by any documents
         suitable to protect Bill Massey and CWK from any and all legal actions
         related to what is now the Applegate lease obligation.

     9.  Should CWK successfully sell the Canadian PPV assets before the
         Chequemate restricted Shares become saleable under Rule 144, then the
         total proceeds amount shall be credited to Chequemate in the form of
         restricted Shares to be released to CWK and Chequemate from escrow. The
         value per restricted Share credited to Chequemate will be $3.00. For
         example: if the total proceeds from the sale of the Canadian PPV assets
         are $75,000, then Chequemate will receive 25,000 shares from escrow
         with the remaining 15,000 shares going to CWK.


Signed:                                Signed:

    /s/ Bob Hahn                       /s/ J. Michael Heil
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Bob Hahn                               Michael J. Heil
CFO, Cinema Internet Networks, Inc.    CEO, Chequemate International Inc.