Its design is very good, and great interaction with elements of the scenario. congratulations.
I have some small doubts:
1 - You are only using Blueprint, or doing this using C + +?
2 - Could you explain a bit how you did the gravitywall (as the ball can only use gravity that space near the wall).
3 - also explain a little about the process, to make the floor boards join, when the ball is close by (I like this effect, very good).
But if you can not explain, all right.
Again congratulations for the great project, I’m waiting for new updates.