The br21m.zip file you have requested: Maps Levels Missions / Deathmatch / BR21M - 200.39kb is not available. Perhaps try browsing all files for the game Quake and upload any files you want to share or are missing. This is the only information we could locate:
The 24 bit textures in the second screenshot come from the FuhQuake 0.31 installer. The skybox used in both is unit6 from Quake 2. Samon has released a new DM map, a remake of the Quake 2 map Q2Duel5 by Retinal.