When playing multiplayer, I am unable to start the match if I select almost any of the modded units, it greys out the ready button and says on the lines "You must select units to start the match". It happens to anyone I play this mod with, what do I do? thx xD

-- Update ---
perhaps it could be that I do not own all the DLC, there are a few clan DLC's that I have no interest in getting, is that the cause? I am however able to use any unit when playing alone