I just tried enabling the cheats by adding the word "cheat" after the target path in the shortcut.  And no I didn't forget to add a space:

"D:\Program Files\Stardock\TotalGaming\GalCiv2\Twilight\TALaunch.exe" cheat

I also ran TALaunch from a dos prompt with the cheat argument.  Both variants started up normally but I can't get the cheats to work.  Any other special trick?  I just tried a few such as ctrl-m and nothing seemed to work.  ???

I'm running the latest patch to ToA (just downloaded it).