Migs,
I'm the one that sells an X-cart Pro to X-mall conversion. From the little bit you've described it sounds like something you may want to consider for a solution. You can find the product here:
http://www.bcsengineering.com/store/customer/home.php?cat=15
The thread balinor is talking about is here:
http://forum.x-cart.com/viewtopic.php?p=74690#74690
Hope that helps.
Carrie