Backend Error: Forbiden - You don't have permission to access /administrator/index.php on this server.

Hi!
I am using the 1.5.3.200 free version of Komento to evaluate, and before you ask, yes I already tried to update it to the most recente version and the problem still happens.
When I access the Integration Module, then go to Joomla Articles or any other Integration plugin installed, I can't save it or press the cancel button, if I do it a receive a white screen with the following message:

Forbidden



You don't have permission to access /administrator/index.php on this server.



Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

Here are my specs:
PHP Built On Linux hm4734 3.2.46-grsec-8.yos.x86_64 #1 SMP Mon Oct 14 17:23:19 BRT 2013 x86_64
Database Version 5.1.54-rel12.6-log
Database Collation utf8_general_ci
PHP Version 5.3.14
Web Server Apache
WebServer to PHP Interface cgi-fcgi
Joomla! Version Joomla! 3.2.2 Stable [ Ember ] 6-February-2014 16:00 GMT
Joomla! Platform Version Joomla Platform 13.1.0 Stable [ Curiosity ] 24-Apr-2013 00:00 GMT
User Agent Mozilla/5.0 (Windows NT 6.3; WOW64; rv:27.0) Gecko/20100101 Firefox/27.0

Any ideas of what could it be? I already asked my provider if they have some sort of security module enabled that may cause this, but they said that they didn't receive any complains about their modules, and that they can't help me with my CMS application, once what happens there is my responsability. Now I am in the middle, where the provider says is my (or the deveoper's) problem and a possible answer from you, saying that this is some sort of security module. Please, I need some help, once Komento is the only Component that is behaving like this. I am considering to buy a subscription, but it has to work properly.

Thank you very much.