I don't think this problem was always here, but while playing tonight, i went to eat dinner...3 times. each time i came back, i found that when i brought my pc back from screensaver, TA had crashed.
i took a look at my debug.err and noticed a 2 things:
 
1. it seems like it's looking for an EU registration on startup...i don't have EU!
2. "Debug Message:  WM_CLOSE message received." <----i didn't tell it to quit. i think the bug is that the game receives a close message when windows goes into screen saver. (i have XP so i don't know if it happens in vista)
here's my debug.err
Debug Message:  *********END dxdiag info.*********
Debug Message:  Entering WinMain
Debug Message:  ******* Starting Game Shell *******
Debug Message:  Could not open reg key HKEY_LOCAL_MACHINE Software\Stardock\Drengin.net\GalCiv2UL
Debug Message:  Could not open reg key HKEY_LOCAL_MACHINE Software\Stardock\Drengin.net\GC2EU
Debug Message:  Preparing to change display settings.
Debug Message:  Using hardware vertex processing
Debug Message:  Using multilsample setting: D3DMULTISAMPLE_4_SAMPLES
Debug Message:  Attempting to create D3DDevice at resolution 1024 x 768, Windowed: 1, Multisample: 4
Debug Message:  Game Resolution: 1024 x 768
Debug Message:  Running in windowed mode.
Debug Message:  HAL (hw vp): ATI Radeon X300/X550/X1050 Series
Debug Message:  D3DPRESENT_INTERVAL_IMMEDIATE
Debug Message:  Refresh rate: 0
Debug Message:  Bit Depth: 32 bit.
Debug Message:  *********Checking D3DDevice Caps***********************
Debug Message:  A full-color cursor is supported in hardware at high resolution modes.
Debug Message:  Border size reported as 6 by 32
Debug Message:  RGB in format 6:6:6, Masks reported as ff0000:ff00:ff
Debug Message:  Now windowed.
Debug Message:  Shell initialization complete
Debug Message:  GalCiv2 is activated.
Debug Message:  ***** Initializing Game *****
Debug Message:  Timer Frequency is 0 b25f4cb0
Debug Message:  Could not open reg key HKEY_LOCAL_MACHINE Software\Stardock\Drengin.net\GalCiv2UL
Debug Message:  Could not open reg key HKEY_LOCAL_MACHINE Software\Stardock\Drengin.net\GC2EU
Debug Message:  No files found matching mask C:\Program Files\Stardock\TotalGaming\Galactic Civilizations II\GalCiv2\./Data/ShipTemplates/\*.shipcfg
Debug Message:  Initializing sound card.
Debug Message:  initailizing bink
Debug Message:  No files found matching mask C:\Program Files\Stardock\TotalGaming\Galactic Civilizations II\GalCiv2\DarkAvatar\Movies\techs\*.bik
Debug Message:  No files found matching mask Movies\techs\*.bik
Debug Message:  No files found matching mask Gfx\Tutorials\*.bik
Debug Message:  No files found matching mask C:\Documents and Settings\Dovie\My Documents\My Games\GC2TwilightArnor\Gfx\Movies\*.bik
Debug Message:  No files found matching mask C:\Documents and Settings\Dovie\My Documents\My Games\GC2TwilightArnor\sfx\*.wav
Debug Message:  No files found matching mask C:\Documents and Settings\Dovie\My Documents\My Games\GC2TwilightArnor\Music\*.mp3
Debug Message:  No files found matching mask C:\Documents and Settings\Dovie\My Documents\My Games\GC2TwilightArnor\Event Music\*.mp3
Debug Message:  Create setup screens.
Debug Message:  Clear galaxy settings.
Debug Message:  Clear influence.
Debug Message:  Clear up laws.
Debug Message:  Clear first time events.
Debug Message:  Clear wonders and trade goods.
Debug Message:  Clear sector mapper.
Debug Message:  Set mouse.
Debug Message:  Set update timer.
Debug Message:  WM_CLOSE message received.
Debug Message:  GameUninitialize start
Debug Message:  Killing Galaxy
Debug Message:  Killing threads.
Debug Message:  Kiling civs.
Debug Message:  Killing ships.
Debug Message:  Killing rallypoints.
Debug Message:  Killing misc objects.
Debug Message:  Killing stars.
Debug Message:  Killing anomalies.
Debug Message:  Killing asteroid fields.
Debug Message:  Killing asteroid field mining bases.
Debug Message:  Killing space resources.
Debug Message:  Killing ascension crystals.
Debug Message:  Killing colonies and planets.
Debug Message:  killing scenario.
Debug Message:  Clearing Turn Event Log
Debug Message:  Clear galaxy settings.
Debug Message:  Clear influence.
Debug Message:  Clear up laws.
Debug Message:  Clear first time events.
Debug Message:  Clear wonders and trade goods.
Debug Message:  Clear sector mapper.
Debug Message:  Clear data definitions.
Debug Message:  Killing ship styles:
Debug Message:  Killing Galaxy: Completed
Debug Message:  Shutting down sound system.
Debug Message:  Clearing sound and music handles.
 
-Dave