Super Mario Bros. X Forums

Upon trying to place warps, it always deleted the previous warp placed in the session. Thus rendering it impossible to place new warps.

Make sure you've placed an entrance and an exit with the same number

If you use both entrances at the same time it will delete the previous one... so make sure to place the entrance first and then the exit. Then you can add another warp.

Oh, oops. bossedit8 had it right, I was stupidly placing the entrances one after another.