The future of Mouseland is saved! :)
I managed to get all 50 pieces of cheese and reach the end of level on the third try. Game is simple but nice.
Some slight improvements could be made in controls and collision detection. Movement should be a bit more agile with less inertia. As of now it's really hard to stop on time before falling or bumping into a cat. Squeezing through one tile passages is hard. It seems there's only a pixel of leeway there.
Great job overall!