strategyonly
C2C Supreme Commander
EDIT: as you can see from my screenshots, I've been able to place every single new unit in-game using the world builder, and this morning I did it all again, so I don't think that ROME has any faulty art defines. Additionally, if the game doesn't find a .nif file at the specified path, the game does not crash - instead it displays that infamous red blob.
That is sometimes true, but putting a unit in game does not always mean it works, i had the same problem with the mod Dragonia II, all units in the WB worked, but ingame playing was a different story, ONE unit caused it to CTD, never could really find that ONE unit