Hello,
Looks like I've discovered an issue with rtMedia rtmedia_uploader shortcode. Whilst working fine on normal "static" WP pages it doesn't seem to work on pages with GET variables set, e.g.:
Works fine if invoked on http://mysite.com/testpage/
Doesn't work if invoked on http://mysite.com/testpage/?action=edit
The issue seems to be related to how the POST request is made when uploading media files. When uploading from a page with GET variables set the POST request URL looks like this: http://mysite.com/testpage/?action=edit/upload/ Please note the /upload/ being added after the ?action=edit GET variable section.
Any advice on how to fix this issue would be very welcomed 
Regards,
Anton.