Thanks. I was able to find the cause and the solution for this issue.
The cause was that your server was giving a 500 error when trying to load some of the files which are located under the kfm folder:
and the solution seems to be to delete the .htaccess file which is in the kfm folder.
I have already deleted the .htaccess for you, so give it a try. For future use of PowerCMS please remove the .htaccess file which is located under the kfm folder.