Finally finished it and 12500 seems to be the highest possible score here. I also created some 'walkthrough' pictures for this game, but I think uploding them would definitively be wrong for this game
This game is really insane. Took me already so much time to finish "only" 4 pictures. Well to be exact, on the 4th picture is one mistake I simply can't find now. Will try another time.
(Short/useless comments don't award GIPS)