The normal dedicated server hosting guide found in the Player Guide had a few errors which I'll try to correct in this addendum (this is basically the same guide made simpler).
First of all, you don't need to copy the DMMapList.txt file to the Content/DeathmatchPro folder. The game will automatically use the correct file in that folder. Just launch the mod, go host a normal server, and set the map list to your liking and press accept. This same list will be used when hosting the dedicated server, so if you had hosted a server before, it would use the same maps for the dedicated server.
Here's a revised final guide for hosting dedicated servers:
(0.) Launch Deathmatch Pro, go to host a normal server and set the map cycle to your liking, then press accept/save. The same map list will be used for hosting the dedicated server. Alternatively, create a DMMapList.txt file to your Content/DeathmatchPro folder with correct filepaths for the maps you wish to use (e.g Content/SeriousSam2/Levels/Multiplayer/DMPro_Mountain Pass/DMPro_Mountain Pass.wld).
1. Create a config file you'd like to use for hosting the dedicated server (see the Player Guide for more details). If you don't care too much for customizing or don't want to edit the files yourself, you can download an example config file from here, which has most of the new DM Pro features enabled except for forcing all players to be Sam. Runs normal DM, 20 mins per match, 50 frag limit, 3 sec respawn limit. (Note: You may need to change the starting map to the map which is first on your map list)
2. Select "Start Dedicated Server" from the mod launcher.
3. Set a name for the server and select the config file you wish to use (if you want to use the example config file, use the FinzyConfig.cfg file you downloaded in step one).
4. Choose "Okay". The dedicated server interface will now start and wait for players to join the server. If you wish to stop hosting the server, simply close the interface. If you wish to join the server yourself from the same computer, leave the interface open and start NORMAL Serious Sam 2 (it will launch the game in Deathmatch Pro since the files have already been replaced by the launcher). For additional information, see the Player Guide.
