same issue here
I would use filezilla or another dedicated FTP program for large uploads to the server.
Dreamweaver is OK for small uploads, but even then, I dont trust it as far as I can throw it to uploading correctly.
I have products_results_xml.php already uploaded so that file is not the issue.
site is amtcgear.com.au
and it is only in categories with more than 10 items that the next button does not work.