Given the specific requirements of Mechanic's liens and the consequences if you screw it up, you should get with your construction attorney. Any good general contractor has a construction attorney on retainer.
If I had to guess, the lien is against the Association because it is is the association (the entity) that owns the common areas. However, I question whether a Mechanic's lien is even worth it, the common areas of an association have no real value. I think you are looking at a relatively routine breach of contract lawsuit.
However, I am just speculating, you need to review your options with a construction law attorney in your area.