Extracting materials ?

Hello guys.

We're a group of 6 students working on a Machinima project on Team Fortress 2 and we're gonna use some custom maps to render it.

To explain it shortly : When using custom maps on Team Fortress 2, they're loading ressources and the map is complete ingame. Not a single problem appears, not a single graphic problem, no textures are missing.

When we use Hammer, some problems appears : textures are missing, Errors, etc ..

So here are my questions :

1) Can i extract materials from a map .bsp ?

2) For example, i played on koth_nightclub and everything was good. When using the map on Hammer, lot of things were fucked up. Can i get the materials a map is using in Team Fortress 2 ?
Like extracting them in a location and putting them somewhere else ?

Thanks for all answers !

Hello guys !

Yeah sure, we're gonna ask for permission about using the maps but for now we're just making a lot of tests.
To be honnest, we don't want to use these materials to make our own maps or what, it's just to render them when using another software. (SFM, i don't know if it's legal to speak of it, so let's talk just about the initials). When launching in TF2, all textures appears and on Hammer (and SFM) lot of em are missing.

And thanks for GCSFScape, we're making some tests actually but it seems to work on some things but it did not solve every problems. But your answers was just what we were looking for.

Thanks everybody ! We'll target the problem and solve it now with your help.