Very good! My main issues was that there was a bug if you and the companion cube is on a plate at the same time and you step off it, then the plate deactivates. Also it was a bit hard to figure out when it was possible to resize stuff. If it is when you have line of sight, then I think drawing a line from the player to the cursor would be a good idea.
Anyway good game! If I have completed the content "so far", then I hope there will be more in the future, because I would definitely play it!