That BSPZIP tool is pretty handy, but it still can't best VALVe's soundscapes...

With the release of BSPZIP, mappers can add custom content and extract
BSPs the content already stored. However, as far as I can tell,
you still can't add soundscapes to it. I added a custom
soundscapes_manifest.txt and a test soundscape to the /scripts section
of the BSP. Surprisingly, this little bit of information is
ignored by the engine. So much for modularity.

I program a little, and it boggles my mind how VALVe could possibly
manage to take such a vital part of their gaming engine and prevent
mappers from adding to it. It sure would be nice if either
someone else could try this and get it right (doubtful, I'm sure I did
already), or if we could contact VALVe somehow and ask for this simple
feature.

BSPZIP? You can open them with WinRAR...

TALK ENGLISH YOU FOOL! What are you on about?