Carlos,
Unfortunately, I don't have a feature to turn off the RPG parts yet. The RPG parts are spread around in the front end and the backend.
The format() function in ajax_act.php file can be modified to remove the various slash ("/") macros.
The getHelpMessage() function in js/ajax_im.js can be modified to remove the slash ("/") macro help message.
The plugins/ajaximrpg/bsheet folder can be deleted to remove the character sheet plugin.
Is that good enough or do you need additional advice?