Ahhh.. I talking with you.
You know, your site is just hard to figure out. It seems like it should do well with our site because it's not too hardcore, but I will tell you this: we don't seem to do very well with celeb traffic. We've tried exiting some traffic to celeb sites with very poor results.
I'm at a loss for why your traffic doesn't convert with our hosted galleries, but you should obviously do what's best for you and maybe that means not using Mac and Bumble. After all, you've got to go with what works.
In looking at the stats, those clicks in the 'VIP' category are how many people viewed the galleries. The clicks in 'VIDEO' and 'DEFAULT' are how many clicked through to the tours, which is a lackluster ratio.
Also, we are also popping a 5-minute free trial console (email verified, which you get credit for) and you don't have very many surfers taking advantage of that which is surprising.
Another suggestion would be to take our pictures and make your own galleries (following the rules at
http://www.bumblecash.com/rules.html).
I still don't know definitively where you get your traffic from. Mac and Bumble does very well with SE traffic (witness this thread and other threads) so I'm skeptical, but I always feel bad when we (as a sponsor) don't work out for someone. We do all we can to convert someone's traffic but if it's just not the right traffic, it's not going to work.
Bottom line is, I would say your traffic isn't working with Mac and Bumble and you should send it to another sponsor. I would recommend Twistys - Shap seems like a pretty good guy and I hear his stuff converts well.