You are a cyan player, use arrow keys to control him. Avoid the brightly red squares! Use mouse to build, X to erase blocks and B to change blocks. (sry physics issues, because 3.0 ruins physics so i changed size of player in v1.1)
Thanks to Thetriplet aka Chooseusernamelol on EE for his Gamemaker project "The Bob Game", which he's still working on!