I'm so not used to "Find the differences" puzzles having movement... or colour for that matter. The trains and the deer were nice touches, and the 'mirror image' style of difference puzzles are an interesting twist. My biggest gripe is the inconsistency of the differences. Some times, after you find them, both sides change to the way it originally was on the left side, and sometimes it changes to how the right side looked. One side should always be the 'correct' side and the other should have the differences, I say.
Lots of furious clicking. Good thing I'm getting a new mouse this weekend.
 "Fields Of Logic"){kind=icon}
 "Electric Box"){kind=icon}
 "6 Differences"){kind=icon}