I really like the amount of UI stuff you implemented in here and how much information you're trying to convey to the player. There are some small things like select button being barely visible over normal text (you should be able to just click on it intuitively), and the bottom right corner having a VERY small display of what is forbidden. But I liked that the color of the slots actually corresponded to the field that disabled them (I made that connection before ever noticing the bottom right, if that means anything). So I suppose the biggest issue is proper UI scaling and readability. But the gameplay itself was perfectly fine and it manages to be a rolling ball without feeling out of control, as it was somewhat snappy and the amount of momentum feels about right. I also did not know how to move down, and never figured it out, but that's okay - maybe edit your description?