Think about that for a second, ,Cat. Would YOU build a hanger with a glass door?
There's another shader you can use as well, in the Doomgiver texture set. [Forcefield] I think it's called...
Oh, another thing Cat... You MAY want to mention that your func_wall is a SP feature - not MP. For an MP map you just construct it like you would for glass, only using a diff texture.