[Windows Mobile Apps and Games] RoryB:
From Wizard Wiki:

Set default SIP

The default SIP (Secondary Input Panel) on practically every device is the Keyboard. You may prefer entry with a different SIP. If so, you can set this to be the default SIP through:

HKCU\ControlPanel\SIP\DefaultIM = |SIP ClassID|

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The |SIP ClassID| will depend on the SIP's ClassID, which may vary per-device. You can find the correct ClassID by searching for "IsSIPInputMethod" in HKCR, then going to the top key and checking the name of the SIP that's in the (Default) value.

Please note that this doesn't work with all SIPs. Transcriber/Calligrapher are two examples of this.

You can, however, set Transcriber as the default SIP by starting Transcriber.exe on startup. (This should be moved to, or added to, non-registry Tweaks page)

WARNING: Do not assume that the below ClassIDs would be -as found- on your device! Setting it to a non-existant SIP may prevent your device from booting up!

WARNING: If you set an invalid value in DefaultIM (or apparently if you're running a recent AKU http://xdaforums.com/showpost.php?p=1032402&postcount=800), then you'll probably have to hard reset your device. NOTE: An alternative means of changing the default SIP is by using the SIPChange utility: http://xdaforums.com/showpost.php?p=995883&postcount=16

The following are some of the ClassIDs typically found:

Typical pre-installed:

{42429667-ae04-11d0-a4f8-00aa00a749b9} = Keyboard

{51A2CB38-154E-4C92-A625-A83871C99EC2} = Phone Pad

{42429690-ae04-11d0-a4f8-00aa00a749b9} = Letter Recognizer

{42429691-ae04-11d0-a4f8-00aa00a749b9} = Block Recognizer

{F0034DD0-2AD4-11d1-9CB0-E84BE8000000} = Transcriber

Third Party:

{991A1001-9DCB-11d3-B3C2-000000000000} = AccessPanel

{1E03E205-12D7-4d82-963E-C01889F2EC10} = Claviature

{500AEF94-EBB8-11d4-B1F8-00304F06E973} = Decuma Alphabetic (UNCONFIRMED!)

{95BDB641-772F-11d2-AC6B-204C4F4F5020} = Fitaly

{52429695-AE04-11D0-A4F8-00AA00A749B9} = FleXslide

{4EAD10BD-83AC-44b9-99AE-71958C1B0F0E} = InPad

{C099F78A-924E-4814-A8CF-54E7BD8C2124} = JetKeys

{4128DEE4-EE84-4338-A261-CC704CB32C19} = NanoPad

{42429695-AE04-11D0-A4F8-00AA00A749B9} = NullKB

{BB25F2EB-688C-4698-ADFC-F422A148AD4F} = PCM Keyboard

{025ECAC2-075B-4b82-A972-05E4C17719EA} = PDAMedia Excel

{FA957346-A925-4b68-B9E1-D3D0310F4433} = PDAMEdia KBD

{DE6510EF-6691-401D-B1D3-B9074BFD1555} = PHM Character Map

{81FC2CAD-AD71-4793-9464-36D27630E584} = PHM Clipboard Pane

{9DD23292-0AB3-48F2-A245-0713652A8CEE} = PHM Ext. Keyboard

{FFFD6819-FF21-4e93-B844-A1BBF986B55C} = QuikWriting

{991A1000-9DCB-11d3-B3C2-000000000000} = RapidCalc

{A070BE16-AD56-11d3-BC77-00C06C512035} = Resco Keyboard Pro

{7F0854D9-9ADA-45A9-A3A2-189D9BE8A653} = Smilies Input Panel

{26F56EF0-2CE8-4C46-ADC8-FE0A7DF12DD1} = SPB Fullscreen Keyboard

{5efab5bd-0af5-48f8-abec-6f36e3a0b5af} = TenGo

{8A7968F3-677B-4F64-859C-8A49FCCCB9BF} = TextPlus

{A5304BFA-CC1D-493f-87D3-D9C17147FA32} = TopKey

{4345EA53-B8A5-4E24-A14A-F7C34DD78077} = WordLogic

{42429695-AE04-11D0-A4F8-00AA00A749B9} = ZoomBoard (OLD VERSION uses same as NullKB, they interfere)

{E2452E3B-2823-4309-90CB-8787C4BA3AF7} = ZoomBoard (NEWER VERSION)
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Add/remove items from the SIP list

If you have a few items in your SIP list which you don't use, they can be removed from the list by setting the IsSIPInputMethod for each item you want removed. To remove the SIP from the list, replace the $SIP_CLSID$ in the example below with a CLSID from the Set default SIP tweak.:

HKEY_CLASSES_ROOT\CLSID\$SIP_CLSID$\IsSIPInputMethod\(Default) = 0 (DWORD decimal)
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To add it back to the list:

HKEY_CLASSES_ROOT\CLSID\$SIP_CLSID$\IsSIPInputMethod\(Default) = 1 (DWORD decimal)
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Edit Word Completion options

If you wish to turn off Word Completion, or change the number of entries it shows, here are 2 good places to start.

HKCU\ControlPanel\Sip\SuggWords (DWORD hexadecimal) (0 = none, default is 4)

HKLM\SOFTWARE\Microsoft\CompIME\SuggWords (DWORD hexadecimal) (0 = none, default is 4)
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