Well the conveyor belt one was a shock to me, but luckily it was an easy fix! I've also submitted a new version that has a delay when changing direction as that was an idea I was toying with earlier and decided I should give it a go!
As for movement I'm just using an off the shelf HTML5 gameboy emulator and the defaults are both WASD and the arrow keys being bound to movement, arrow keys might be more comfortable! The character size was intended to be part of the challenge but I'm unsure if it's worked out in an intuitive way, it really does give the vibe of banging your head on everything
Thanks for the feedback! You absolutely helped me squash a bug that although hilarious was quite broken (it also counted towards victory so you could just shove pieces of converyor belt in the lift zone and win without dealing with hazard boxes)