For the track "u got trolled", I put a star directly beneath the rider, did the track, clicked publish, clicked cancel, did the track again, clicked publish, clicked cancel, put a line that cuts through the rider to make it impossible, clicked publish, and clicked upload. Make sure that your track size isn't too small, though!

I've found a bug that even if you don't use the trick and you did it, when you click publish you will realize you can't publish it and you will have to do it again. So before you do anything to the make impossible, click publish and if it says you can't publish it click cancel and do it again. Then make it impossible, and it should work the second time.

For example, if you made an extremely difficult track, you can add a portal that directly gets you to the star, complete it, then erase the portal and you can still publish it.

kewlaids ok, so, you have to first complete a track. Then you can add or erase anything on the track and the game will still think you did it.