I had similar issues so have tried a few different things to help me control the traffic and adjust things till the page converts.
1) I made a lading page for the sponsor and sent traffic from the free site there, from here I linked direct to the join page.
http://www.inbedwithfaith.org.uk/faith/2/
2) This one I just started but I link to a hosted gallery
Another thing you may want to consider is adding a product link too to your free sites, again its something I have only been doing for a month and the odd sales the product gets really boost the bank ballance.
http://www.free-indian-porn.co.uk/de...1/gallery2.htm
Its too early for me to say which works best though I cerntainly have seen good returns on the product link.
