No story and crappy dialogue ruined this game. Fix those two aspects and the game gets a solid 5/5 from me. Amazing art. But seriously? "The museum is under threat"? Wow. Also, if you click on one difference and it stays there then on the finished picture it's not there and vise-versa.
Last level little secret. Top left ground level border is a map.
3/5 Fun little time waster. Though I hated the graphics and it felt extremely unrewarding.