aluinie: I have always downloaded my gog purchase after buying it even if i dont plan on playing it just then. Backing it yp on external harddrives. I recommend doing that for anything that you could lose if your pc hard drive crashes as i have seen people lose precious photos by not backing it up.
I Wish there was a list of games removed on gog or an announcment prior to a game getting pulled to warn people of it would save a lot of hassel.
I believe the gogWiki folks keep such a list and usually GOG try does warn people. Sometimes that's not always possible, but GOG has still not commented on this even after the fact ... maybe because of the forum title they don't know to stop by ... or maybe they're still waiting for something to happen, legally or professionally, before they release a comment.