Tip: Layer 3 backgrounds and tides disappear when you hit a message box, so plan your level around that. For example, you can add a sublevel without layer 3 at the start/midpoint, and include your message there.
This is my submission to the GreenDeathFlavor level design contest. The objective was to create a ghost house level. Its gimmick is juxtaposing the eating blocks with the ghost sprites. The level has three sections and two checkpoints.