Visit my website www.TimRichter.de for more maps and music of mine ;)
gm_BlackMesaSigma_Night by Freakrules
Visit my homepage www.TimRichter.de for feedback, more maps, music and other stuff by me ;)
How to install:
Take the whole folder "gm_BlackMesaSigma_Night"
and put it into your addons folder, so the layout will look like the following: