Gridsnap not working and militia skybox

Map problem #1

I’m having some problems with the grid snap feature in source SDK, The blocks I create Does not snap to the grid if anyone has a fix for this please tell me.

Map problem #2

I’ve been wondering “How would I be able to put in the militia skybox?”
I look at the great maps and see the militia skybox in effects and would like to know for myself how to get it.

If anyone as answers to my problems please tell me

Press shift W

Go to map>map properties and for skybox texture name put militia_hdr