1. Not sure what you mean, but I think you would just compare the x value. Like spite.x< n.
2. Depending on your movement style you would just reference sprite.y + n amount.
3. There are 2 way I can think of, but until families, or containers are implemented it can be a bit tricky. Right now for the first method you could add a bunch of sprites to be the barrier, and have them always set position offset from the main sprite. To do that you would need to use index's like barrier(0)set position to mainsprite(0).x+n,mainsprite(0).y+n, and barrier(1)set position to mainsprite(0).x+n+n,mainsprite(0).y+n+n. For the second, which is easier, you can make a bunch of frames, and have that non moving animation set position to the main sprite. Then on collision you just change the barrier's frame to the next.
Also Ninja Yannnewt2011-12-08 17:45:16