How to change skybox texture in GM_black.

I’m running GM_black and i’m wondering if there is a way to change the skybox texture for posing.
I know there should be a way.

You can, sv_skyname, requires restart.

Do i just type that in, then start the map again?

Pretty much, if the map actually has a skybox. sv_skyname painted for example will allow you to use the sandbox sky editor.

can someone link GM_Black for me, can’t find it ANYWHERE

Here you go https://dl.dropboxusercontent.com/u/206956179/gm_black.zip