Does not work with Lion on my MacBook Pro

I just bought this app, after buying it for my iPad. Now I learn that there is a list of Mac computers that this software does NOT work with. Mine is in the "doesnt work" list. Avatron claims it is due to an Apple bug, but this doesnt solve my problem. I would simply like my money back, because this should have been explained up front. How do I receive a refund?

D. in Canada about Air Display®, v1.4