Cool art, interesting concept but man those controls. I did manage to get to the companion cube reference and I vibe with that but pushing those cubes around was a darn nightmare and at one point, the companion cube got in the lazer and I spent a good 5 minutes trying to get it out and finally did but it was very hard.
Jumping on your corpses was also tricky, besides the likelyhood of having to create a dozen of you to just jump 3 steps because your corpses wont stop rolling off, every now and then, you get launched into the skies. Or every now and then your jump kinda lags you in space preventing your character from moving. Like making the character more cube like and less capsule like could help a lot with this.
There was also a time when I got pushed into the wall or the cube got tucked into a corner making it impossible to get out.
And there were times when you couldnt see the player or cube due to objects in front of the camera.
I know I kinda wrote down a lot here but I do want to say that I lvoe this concept, I had a lot of fun playing this and only towards end did I encounter some bugs in the maps like walls that appeared like they shouldnt be there or platforms that had no mass/colliders.
I seriously love the concept, it rocks and with more playtesting and patches, this will be a rockin game! Keep up the good work to all 3 of you!