Thanks for the comment!
Custom control schemes would have been nice, but was not the focus of my game. Other people also suggested different control schemes.
The level names are a combination of the number of blocks on the tile, a lowercase x (which the font only displayed in uppercase/big), and a letter/symbol that has some resemblance to the shape. So the common tetris shapes are name 4xT, 4xS, 4xL etc.