There is a problem with the jQuery version downloaded from Google (seems to be v. 1.9.0). I solved this by going back to Wordpress' version of jQuery. In rt-framework/classes/theme.php i commented out line 44 and 45. I guess this could also be solved by specifying the version in the Google API call...
I encountered the same issue. At first, the solution recommended by flojon did not seem to work but when I updated WordPress to the latest version and then updated the theme.php file. The solution worked.