Got a game over on the Panic Puppet Act 1 boss right now and took a break. The level design often has those awkward space-filling zig zags that can make it confusing to navigate but I love the effort you put in recreating mechanics and setpieces from 3D Blast into them. The boss fights are the game's strongest point; I had a ton of fun fighting the Gene Gadget 1 boss and was sad when the "other two" didn't come out to play right then.
Only thing I didn't like so far was the Special Stages. You've recreated the Sonic 2 half-pipe here but the controls just feel wrong.
Really, great work getting this finished!