Yeah its been an on going bug, easily done when you are messing about the files... But i will wait until you update it before i have a crack at a campaign. The bug is listed here, but will list again. It seems to be all the new units in the celtic culture and those factions that share these types of units the bug crosses over.
Celtic.
Highland Archer
Levy
Speerman
Brigade
band
Woodrunners
Warband
Warriors
Fianna
Teachers
Axeband
Axe Warriors
Bows
Arcers
Highland Archers
Elite Archers
There us probably more too ie.. Caledonians have the same missing units.