This is the kind of game I want to see in game jams!
Love to see custom engines and especially ones that allow the enduser to customize the game.
Getting that lava frog down the hill was quite tricky, to the point where I tried to go into the engine and give the frog or the fly more live. I got a bit lost while trying to figure out how to achieve that and ended up going back to beating the game in its vanilla state, but the look under the hood was still a fun experience.
The idea of playing both frog and fly and the cute worked very well and the graphics were cute. Top marks in all categories =)