source sdk trouble

Its been a hoby of mine making maps in source sdk and then playing them but when i tried to make the sky box in my latest map (which is hosties and awesome) I couldnt make it hollow and I cant make it run. I know it has to do with the update but i cant figure out how to do it. I usually press control H to make it hollow but instead it deletes the map. If there is anybody here that knows SDK well can u help me out please.

I already tried google, valve, and youtube and it doesent explain I would really like to add a skybox so i can try out my hosties map and the gg map I made. It may have something to do with the 3d skybox but im not sure.

seperate the cube/box of your map, delete the roof (top) of the box, replace it with a brush of skybox. No need to make it hollow

Run it on a mac

That Guy wrote:

seperate the cube/box of your map, delete the roof (top) of the box, replace it with a brush of skybox. No need to make it hollow

the new 3d skybox also requires a camera and I think that a second sky box also do you know how to do that . thanks for your help its a pain but it works