from what i can see in the code, the problem with searching the category would be that the category list does not have any items in it.
This is because the catagory list uses a recordset named "WADADynListproductcategories".
On each page that you want to add the search for to, you need to add the "WADADynListproductcategories" recordset as well.
Create a new recordset named "WADADynListproductcategories" in the simple recordset options, set the recordset to use the CategoryID, CategoryName columns from the productcategories table.