I love arguing so here you both go...
SEO Mike you say that you asked Pax "questions designed to answer questions that could come up from serious buyers". Um... no you didn't. You don't ask a designer "hey, why should I buy your design over a free design". If you're actually looking for a design, you already know the advantages/disadvantages between free and bought designs with full rights. Whether or not the design is worth the price is obviously up to the buyer and the seller. You don't go to a painter and say "hey, why is your painting worth $1000 when I can get a free photo from flikr?" It's insulting and quite rediculous. If you think it should be worth less and you are interested, then you make an offer.
Pax, if you are seriously trying to sell your design, you need to be at least a tad more professional with responses. Sure, this isn't an official marketplace or anything, but your attitude can greatly influence a potential buyer's decision. I'd consider trying to slice the design and have it coded in HTML/CSS so that potential buyers don't have to worry about that step. $75 for that design with it already coded would definitely be more attractive.