I "fixed" the clean URL issue. I just removed the
highlighted text from the code in manufacturerinfo.tpl
Code:
<a href="product.php?productid={$manufacturerinfo.productid}&cat={$cat}&manufacturerinfo">
so that it is
Code:
<a href="product.php?productid={$manufacturerinfo.productid}&cat={$cat}">
There are 2 instances of it. I removed them and the URLs are clean now.