Official fix, courtesy of Hillrop:
https://www.dropbox.com/s/sk2wyqfkweyxxy...b.bsp?dl=0
1. Download the linked bsp file
2. Open the maps folder in for GMod (for those of you using the default C: drive, have Windows 64-bit, and the works, it'll be this directory: C:\Program Files (x86)\Steam\steamapps\common\GarrysMod\garrysmod\maps)
3. Drag and drop the bsp file
4. ???
5. Profit
That should work. It has worked for others.
EDIT: Problem should be fixed. Disregard
https://www.dropbox.com/s/sk2wyqfkweyxxy...b.bsp?dl=0
1. Download the linked bsp file
2. Open the maps folder in for GMod (for those of you using the default C: drive, have Windows 64-bit, and the works, it'll be this directory: C:\Program Files (x86)\Steam\steamapps\common\GarrysMod\garrysmod\maps)
3. Drag and drop the bsp file
4. ???
5. Profit
That should work. It has worked for others.
EDIT: Problem should be fixed. Disregard