No question, but a remark to help others who might encounter something similiar.
There seems to be a problem with the VGA320.drv supplied through
SpaceQuest.net,
which supposed to make some flickering go away, or at least it proved a problem for me
After installing it, SQ4 wouldn't start anymore and just exited with something like:
"You did something we weren't expecting you to do.... Error 4"
After reinstalling the game and ^not^ replacing the driver, everything worked like a charm. I must add, that I didn't encounter the problem which this patch is supposed to fix, so I guess to old credo "if it ain't broke etc." still stands :P