When you say you 'end-task' the game, are you doing it by selecting 'End task' the Task Manager or by right-clicking GalCiv2 on the task bar and choosing 'Close'?
The debug is reporting that you closed the game normally, so I would assume you are right-clicking and choosing 'close'.
You are correct. Once minimized, I right-click the tab, then select "close"
It takes 4 to 5 minutes to do so. On occasion, I do force it to shut down immediately by using the "End Process" command.
But you still have a video driver error, which sometimes can be caused by a flakey monitor driver (as well as the overheating and bad driver install I mentioned earlier). Can you install the correct driver for your particular monitor? That might help to narrow the possibilities.
Alhough I've usually just always stuck with the windows default PNP Monitor driver.
I have a montior driver somewhere that I once downloaded. I'll get it installed. I'll also kill all things ATI from the system, and start fresh with driver reinstalls. Then I'll let you know how it goes. While I diligently clean my PC at regular intervals, I'll do that again too while I'm at it. BTW, all 13 fans in my system are confirmed working (as by visual inspection & hardware monitors).