Addons from the Steam Workshop?

[moo10032]

I got the srcds server installed for Garry's Mod, got it fully working, people were able to join my game and works perfectly. Now I want to change the servers maps to one I linked up through my Steam collection. The server command chat shows it downloads the maps, and extracts them. So I use the "changelevel mapname" to change, and I get the error the maps ".bsp" is not found! There is no such files anywhere around, the only thing that is downloaded into the addons folder is in the ".gma" format. How do I change the map? I've tried everything possible and have been googling around all night long.

Also I am a 100% noob to hosting and servers so explain anything in GREAT DETAIL PLEASE!

Here is the server log:
66.7 fps 0/16 on map gm_construct
Console initialized.
ConVarRef mat_dxlevel doesn't point to an existing ConVar
Game.dll loaded for "Garry's Mod"
Initializing Steam libraries for secure Internet server
Logging into anonymous gameserver account.
Fetching Workshop Addons..
Calling GetCollectionDetails
Connection to Steam servers successful.
Public IP is 75.72.172.11.
Assigned anonymous gameserver Steam ID [A-1:1176249347(3324)].
VAC secure mode is activated.
Collection has 2 Addons
Mounting Addon 'Drivers Heaven' (122109283)
Downloading...
5%
13%
20%
28%
36%
43%
51%
59%
67%
74%
82%
90%
97%
Done!
Extracting...
Mounting Addon 'gm_excess_islands' (115250988)
Downloading...
23%
52%
82%
Done!
Extracting...
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/game_sounds_portal
.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/game_sounds_player
_portal.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/game_sounds_weapon
s_episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/game_sounds_weapon
s_portal.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_sounds_music
_portal.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_sounds_escap
e.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_apertur
e_ai.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_energy_
ball.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_turret_
portal.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_rocket_
turret.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_glados_
cores.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_strider
_episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_turret_
episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_soldier
_episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_roller_
episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_combine
_ball_episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_citizen
_episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_citizen
_ep1.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_zombine
.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_dog_epi
sodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_antlion
guard_episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/npc_sounds_advisor
.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_sounds_e3_c1
7.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_sounds_e3_to
wn.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_sounds_e3_bu
gbait.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_sounds_music
_episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_voices_episo
de_01.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_sounds_after
math_episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_sounds_outla
nd_episodic.txt
CSoundEmitterSystem::AddSoundsFromFile: No such file scripts/level_sounds_c17_0
2a.txt
PARTICLE SYSTEM: Unable to load manifest file 'particles/particles_manifest.txt'

Network: IP 192.168.1.102, mode MP, dedicated Yes, ports 27015 SV / 27005 CL
Executing dedicated server config file server.cfg
Initializing Steam libraries for secure Internet server
Logging into anonymous gameserver account.
Unknown command "sbox_plpldamage"
Connection to Steam servers successful.
Public IP is 75.72.172.11.
Assigned anonymous gameserver Steam ID [A-1:1176716292(3324)].
VAC secure mode is activated.
changelevel gm_excess_islands
CModelLoader::Map_IsValid: No such map 'maps/gm_excess_islands.bsp'
changelevel failed: gm_excess_islands not found