when it comes to multiplayer I mean. getting "failed to uncompress game data"

Had some time to look blue marble files and seems both Blue Marble and RoM change some of the same xml files thus there might be conflicts. So they probably won't work correctly at the same time. RoM2.0 has 'Out of Synch' problem in multiplayer mode when building Colonist/Pioneer, RoM 1.03 should work fine since it doesn't have those units.