Contribution Installation on OSCommerce

Hi, I have installed a few OSCommerce contributions over that past few months on my new website, however, with my latest addition, the SEO-G contribution, i'm having trouble with installation. I have installed the contribution on my website: [login to view URL] But when i enable SEO-G in the admin panel, the links change to SEO Friendly ones, but when you click on them, you get an error, like the page doesn't exist (HTTP 404 Not Found). What i need is for someone to get this contribution to work correctly with some good keywords in the url. I've asked my host and they say the mod_rewrite function should work ok. I hope i've provided enough information for everyone. The link below is for the contribution that i want installed: [login to view URL],5080