It's 15x15, but they will work even on larger maps.
I think it can be made with a smaller amount of CE's, but I'm not sure.
The rules are as follow:
- the player will be warped if the corresponding field on the other side is free;
- the floppies will be warped even if the corresponding field on the other side is *not* free, in this case they are destroyed in the hyperspace;
- after being warped, the floppies are pushed one field away from the warp border as soon as that second field is free;
- the floppies turn into emeralds when touching the terminal

Enjoy!
http://www.zomis.net/rnd/download.php?id=399