For the purposes of this review I played the unpatched version submitted at the end of the jam. This means I didn't get to finish, which is a real shame because I really liked what I saw.
There's a lot of subtle level design work here and it shows. It's possible, but harder than you'd think, to unintentionally lose an item. Part of that is down to the level design itself; it's pretty clear when there's a hard gate coming up and when throwing your gear might be a bad idea. Part of that also comes down to the actual physics of the throwing mechanic itself. Thrown items bounce enough to sell the risk of a sketchy throw, but never so much that you ever feel like you lost an item to bad physics or chance.
I was also a big fan of those repulser fields. That introduction especially, where you introduced them as an item gate, then immediately turned around and showed them off as a puzzle mechanic? 
That's some quality game design right there. That's the shit I'd expect to see in Portal. High marks.