Coupla basic questions;

I think I'm being a huge derp with this one, but is there a VMF instance for the checkpoint spawn rooms found in co-op? You know, the rooms usually found after team doors where you respawn if you die after finding it. If there is, I can't find the thing, so...

Secondly, music. Is there a way to fade music around without actually stopping it? I ask because I want to use tracks in sync in the way they were used in the main game, as in the second track fades in when, for example, you are bouncing around on faith plates. I know how to get the output from the faith plates, I just don't know how to set up the ambient generics without the music going back to the start every time it fades out.

Any help would be appreciated, thanks in advance.

As for your music problem, I think they had something else going on in the official maps. I was trying to do the same thing in my map, and it looks like in their maps it just sends PlaySound to the original again. Again, I think they have some entity or script controlling it.

As for the other problem, I don't know all the instances yet, but an easy way to browse them is to open the .vmfs directly so you don't have to mess with the func_instance entity pointlessly.