paint tiles by pressing 1 for selected tiles, and 2 for regular ones. Press q to show level code. When you are done selecting tiles, press space to confirm your choice. move around with arrow keys.
Note: the saving doesn't work yet. version 2: Made the customizer smaller. v2.1: Made level code functionality and list. (Press Q) v2.2: Made level saving, fixed level code bugs, and halved the level code size. v2.3: Add new variable reporters and a Save Button. v2.4: Shrinking animation.