The interface is intuitive enough not to require a translation, but here goes.
Circle pad: rotate
Up: add block
Right: change color
Down: delete block
Hold Left and slide the stylus to rotate quickly at will
L: layer mode
X: clear all
Y: load
A: save
B: undo
It IS SmileBasic and people have been doing amazing things. For just $10 the possibilities are endless. Right now I'm most impressed about Calc84's Spooky Maze, almost Doom-like 3D awesomeness