Good news for all WaW mod server admins - JD from Treyarch has finally come up with a work-around to the 2048 materials error:
We’ve got a tip for those of you getting the 2048 material asset error message when playing a mod. If you have any custom maps in the usermaps folder, the game automatically reads them for you, so they can be added to the map list when starting a server, and to the ingame votemap menu. In order to skip this automatic process, you need a mod.arena file. The arena file will be read instead of the usermaps folder, and only the maps specified in the arena file will be added to the map lists.
It is possible to use an empty mod.arena file for the sole reason to skip reading the usermaps folder.
Server admins might want to use a mod.arena file with the maps in rotation if they want the map loadscreen to show in the votemap menu ingame. To get this working, the loadscreen materials must also be included in the mod.ff. The iwd with the arena file will be downloaded by all users of the mod ensuring the users won’t load unnecessary material assets when playing the mod.
The mod.arena file must be inside an iwd in the mod folder. Inside the iwd, the mod.arena file must be at the root.
There are two methods to add the arena file:
1-Drag and drop the arena file into any iwd inside the mod folder
2-Zip the mod.arena file into a new uncompressed zip file in the mod folder, and change the extension from zip to iwd.
In short, Modders should bundle an empty .arena file with their mods; Server admins should keep it updated with their desired map rotation. Users shouldn’t have to do anything if modders and admins do their part.
I placed a blank mod.arena in my zz_demon.iwd file (not in any folder - just at the root), and was able to run mp_burg (old version - not the new one) on my server for the first time. So, it defo works.
It will be better if we actually take the time to fill out the mod.arena file as then the stock ingame map voting will work better (especially if, like me, you have custom gametypes).
Good on Treyarch! So close to the release of MW2, and with all the sadness, a bit of news like this puts a smile on your face, as one of the major headaches in running a WaW server has been removed.