there isnt a maximum team size, but i would recommend to keep it small, as it wont be easy managing a 10 person team with 3 days
you can submit your game early, that’s fine by me, and if needed, you can submit late, just DM me on Discord if you need to submit late
there are no restrictions on game engine or build target, but it’s recommended to build it for web since anyone can easily run your game
if you have any more questions, feel free to ask!