Unreality as the core of your adventure is an ambitious direction. There are a lot of cool ideas mixing around in here and I like how this could spin into other adventures.
That being said, it is going to take some work to get this there. Condensing the encounter table into one, designing concrete ways players can interact with each room, and providing GM facing details for what is going on would be a good way to make what you have easier to parse at the gaming table.
The Cube has potential and I am stoked to see what direction you take it!