Use up arrow to change block. Press space to place a block. (Hold for stream.) Press A to toggle play and edit mode. You should see the hitbox in edit. Thats because it will show you anything inside the hitbox, which will automatically affect the player in play mode.
Thanks to @griffpatch for the cat, its main scripting and its animation (i did the color sensing and the modes) @Yllie for idea Me for all else (extra cat scripting from another project of mine) UPDATE LOG: v1.0 Cat, from @griffpatch . 24 Blocks: Air, Solid, Slope (4), Spike (4), Red, Platform, Conveyor (2), Gate (4), Water, Space, Ledge/Ladder, Bouncy, No Jump, and Finish. v1.1 Finished space, and improved dragging hitbox in "edit" and also shrunk the hitbox, and the block size v1.2 Adding reverse gravity, but I haven't worked out the bug where the character is walking on his head.
