Problem starting UT3 Server with custom mutator

[array2001]

Hi,
I wonder if someone with more experience with UT3 could help to to troubleshoot this:

I am trying to start a server with a custom mutator (for remote C-Sharp bot programming), using this command:

UT3.exe server DM-Deck?Game=UT3Bots.BotDeathmatch?GameMode=0?NumPlay=0?MaxPlayers=16?MinPlayers=0?GoalScore=20?bIsDedicated=False?PureServer=0?bIsLanMatch=True?bAllowJoinInProgress=True -login=MyUser -password=MyPass -useunpublished -log

The server seem to start correctly, but the match never start. There seem to be some problem with custom chars loading. These are the corresponding log lines:

Log: Flushing async loaders.
Log: Family Asset Package Loaded: CH_IronGuard_Female_SF
Log: CONSTRUCTIONING: LoadFamilyAsset (IRNF) Took: -0.69 secs
ScriptLog: CUSTOMCHAR Start: UTPlayerReplicationInfo_0  V01
Log: StartCustomCharMerge: 0.076022 ms initializing, 0.422016 ms texture streaming
ScriptLog: TIMEOUT: Streaming Textures for custom char. UTPlayerReplicationInfo_0
ScriptLog: CUSTOMCHAR Start: UTPlayerReplicationInfo_6  VRed
Log: StartCustomCharMerge: 0.095017 ms initializing, 0.678748 ms texture streaming
ScriptLog: TIMEOUT: Streaming Textures for custom char. UTPlayerReplicationInfo_6
ScriptLog: CUSTOMCHAR Start: UTPlayerReplicationInfo_12  VBlue
Log: StartCustomCharMerge: 0.126407 ms initializing, 0.683431 ms texture streaming
ScriptLog: TIMEOUT: Streaming Textures for custom char. UTPlayerReplicationInfo_12

The thing is that I can successfully start a server in the same machine by starting the game normally and creating a new multiplayer game. In that case, I don't get any TIMEOUT message in the log. However, I need to run the server without any GUI.

Does anyone have an idea what could be wrong with the server command line?

Do I need to put some files in a different location when running as a server??

Thanks!