I really liked the concept of playing the game backwards and also solving the puzzles in reverse. Some sound cues could have been good to signal whether you got to a blaster shot in time. I really like the introduction of new mechanics, it could have been great though to have a final level at the end that combines some of them, or makes you figure out what to do first (or better last) in the level. Like you need an enemy to survive until the end to activate a platform, so you have to kill it first etc.
Great job! If you have the time, it would be great to get some feedback on my entry as well. It's only my second game, so I appreciate every note I can get.