Re: Installing skins.
I'm having the same problem with my custom skins. I know the material paths I'm using are correct because I tested skin in HL2's model viewer; it's just not appearing ingame.
I thought perhaps custom content had been disabled, like Valve has done with their version of Blue Shift on Steam. However, out of curiousity I tried using some custom sounds in SiN: Emergence and they worked. So custom sounds work, but custom skins will not for some reason. If I had some custom models I would like to see if those would work too.
Anyway, I think Ritual has to enable/disable some setting to allow us to use custom materials.