I am just going to give some advice cause I know you are trying hard to get people to link to you. Most people will not use a banner ad on thier site for another site. If you are wanting anything from it you should be using something with anchor text not the image. You will benefit more from that.
Another thing I noticed that may hinder your linking strategy is telling people you will link to them under terms that they display a link to your site on their homepage and in return you will give them a directory link. Unless your site is one of the top sites most people will pass on this one.
Myself I wont do this and I dont care who's site it is whether your PR7 or not, I will link because I want to not because I have to and if I lose the link exchange over it I lose it.
With your directory I would ask that a link be pointed towards your site and drop the banner thing and you may find more success.
good Luck I would comment on your site but I dont understand it
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