Bumper3D: Thank you!
mvotre:
I'm using face select mode to select parts which are connected, split them (y-key). And if the parts join again, I'm using vertex selct (with the see-through option enabled - button to the right of the buttons which switch vertex-, edge- and face-selection modes) and merge the vertecies where necessary. I hope this helps, if not, toss me a pm, I'll make a few screenshots then.