My first SmileBASIC game, Golzeeb! here's the key: RXDEF38J

I just got back to programming this game of mine. I figured out a good way to program the enemies, but I'm still having trouble with the platforms!

FINALLY got collisions down pat. However, my little game world has no danger... Is there a way to code an enemy, and then place MULTIPLE of that enemy? Also, collisions only apply to the TOP of a platform. Can someone help?

How do I check collisions? I've got player gravity down, but the character passes throughthe floor! What do I do to ensure it doesn't happen?

Can anyone tell me how to flip a sprite horizontally? The only thing I could find was SPDEF, and the manual isn't helping.