You can drag the different "planets" around and try to lead them in circles. Just experiment with it. If you find any glitches, feel free to report them to me, I'll try to make this as glitch-free as possible.
So I've got some basic orbiting, but it's very basic. I've got 3 "planets". There's currently no variables for mass, planets cannot collide, and theres only a speed variable for each planet (there should be a sperate variable for speed x and y). Currently, when planets meet they orbit each other rapidly gaining lots of speed. I made this in about 20 minutes, so it's not nearly as good as it could be. I also made this in 1.4 so if there's any problems, I'll blame it on 1.4 regardless.