Subscribe to download
The_Witcher Backgrounds

If its addon not working, you must:
1)Check whether you have subscribed to this addon
2)Try to disable and re-enable the add-on in the game
3)Click on "Gamemodes" and select other Gamemode,then again Click on "Gamemodes" and choose the SANDBOX
4)If this does not work, unsubscribe and subscribe again. After try to do the same again (1-3 Points).

If this does not work , then:
1)Download this background link: https://drive.google.com/open?id=0B3N7wxko4Vxkb3dxNVd1Qno4eDg
2)Copy backgrounds this route: D:\SteamLibrary\steamapps\common\GarrysMod\garrysmod\backgrounds
3)PROFIT!!!
HAVE A GUN AND FUN!!!!