well, pam, as you may have noticed already, you'll get conflicting answers from a number of sources who consider themselves experts.
the law itself isn't really all that confusing. it's all the differing opinions that muddy up the waters.
some pattern makers have successfully bullied buyers into believing they can dictate what's done with the finished product. nearly everything i've read from credible sources says that what you make using a pattern is yours to do with as you please.
most of us agree that, without or without the law, it's always a best practice to give credit to the designer.