I have the same issue. I think it MIGHT be related to enabling the WOTC new promotion screen by default. In the alternate launcher this mod is required for biotic class but when loading I see a warning about it conflicting with RPGO.

Yes, check the main mod page, scroll down to the FAQ - it says which three mods to deactivate, as they are already integrated into the mod, and having them active can cause problems; "New Promotion Screen By Default" is one of those mods. Deactivate that mod, then come back if the issue persists.