This is a little complicated, but this is what I do when in that situation.
1. Open the map.
2. Click on Load Map.
3. Delete the map file.
4. Save the map under the name you wish with ctf_ before it.
5. you're done.
6. go playtest it
7. like now
8. lol why am I still writing steps, just draw a staircase?!?!?!