Need Help With Map KF2 SDK BUG (with screenshot)

[Keedurn]

http://imgur.com/a/TJNle

As you can see my hallways are filled with this texture, doesn't appear on grid and you cannot select it, how can I get rid of this texture so I can walk through my hallways again? Any help would be appreciated thanks!

 

[Seanchaoz]

Looks like you've added a CSG brush. Probably from clicking CTRL+A by accident. To get rid of it you need to wrap it inside your builder brush and click the "CSG Subtract" button (or hit CTRL+S).