The ump-beta 5-28-11.zip file you have requested: Maps Levels Missions / Map Packs / UMP Beta Map Pack - 173.83mb is not available. Perhaps try browsing all files for the game Halo: Combat Evolved and upload any files you want to share or are missing. This is the only information we could locate:
A pack of ten UMP Beta maps that are no longer available on HALO Maps websites. Pack includes the UMP maps ==> Advantage, Assult, Carystus,Chamber, Divide, Legend, Mirror, Purity, Sanctity, Sewrage.
All great maps for close quarter firefights OR scrims.
For HALO Custom Edition