ut2004-redorchestra-3.3-r1 does not list maps in either Multiplayer, Host Game or Practice mode. You can however see UT2004 caching the maps (I guess that's what it's doing) on first load: dave@localhost ~/.ut2004 $ redorchestra Error loading new keyboard description Exporting DM-BP2-GoopGod.....Successful! Exporting DM-BP2-Calandras.....Successful! Exporting CTF-BP2-Pistola.....Successful! Exporting CTF-BP2-Concentrate.....Successful! Exporting AS-BP2-Thrust.....Successful! Exporting AS-BP2-SubRosa.....Successful! Exporting AS-BP2-Outback.....Successful! Exporting AS-BP2-Jumpship.....Successful! Exporting AS-BP2-Acatana.....Successful! Exporting RO-Perekop_SO.....Successful! Exporting RO-Rueckzug_SO.....Successful! Exporting RO-IronAnnie_SO.....Successful! Exporting RO-KorsunAirfield_SO.....Successful! Exporting RO-KarpezosMove_SO.....Successful! Exporting RO-Arad_SO.....Successful! Exporting RO-Ogledow_SO.....Successful! Exporting RO-KrasnyiOktyabr.....Successful! Exporting RO-Rostov.....Successful! Exporting RO-RedGodOfWar.....Successful! Exporting RO-Kharkov.....Successful! Exporting RO-Sevastopol.....Successful! Exporting RO-StalingradKessel.....Successful! Exporting RO-HedgeHog.....Successful! Exporting RO-Kaukasus.....Successful! Exporting RO-Jucha.....Successful! Exporting RO-DieWalkure.....Successful! Exporting RO-Spartakovka.....Successful! Exporting RO-BaksanValley.....Successful! Exporting RO-Barashka.....Successful! Exporting RO-Berlin.....Successful! Exporting RO-Warsaw.....Successful! Exporting RO-Kalinin.....Successful! Exporting RO-MoscowHighway.....Successful! Exporting RO-Konigsberg.....Successful! Exporting RO-Karlovka.....Successful! Exporting RO-Donets.....Successful! Exporting RO-Danzig.....Successful! Exporting RO-Ponyri.....Successful! Exporting AS-FallenCity.....Successful! ...etc...
Well, 3.3-r2 definitely works and was added to the tree just now. Enjoy.