Hello!
Thanks for playing.
What you highlighted here is probably the biggest problem of the game in my opinion and sadly a problem that I didn't get to solve.
It comes from the fact that the whole game was based around you actually BEING ABLE to see what is inside of the cubes but that mechanic proved very technically challenging (I'm not the best tech artist) it took me a lot of time to try it without success and I had to drop it almost last minute.
Now after all is done I have hundred ideas about how to make it work, but it is a little too late.