Add Media not working with WP 3.5.1

I recently upgraded to WP 3.5.1 and just today wanted to try your plugin to see if I might be interested in the premium version.
I have noticed that the Add Media button and permalink Edit button do not work when adding new portfolio item.
I have taken steps to test this on the default theme, and with all extra plugins turned off but had the same results. For normal posts and pages this all works fine.
Any ideas? Thanks.

https://www.ads-software.com/extend/plugins/nimble-portfolio/