Nice map! The screenshpt gives away the answer, but very cool nonetheless. Check out mine: http://steamcommunity.com/sharedfiles/filedetails/?id=123833961

Awesome concept! Very fun to execute.

Easy to complete once you understand what needs to be done, though, and the screenshot you posted totally spoils the map :oP

If you decide to make any updates, you might consider making a way to respawn the cubes, since there is a fizzler nearby and the tester might manage to lose a few of them. It's not a big deal though, since I see there are extras.