Checking/correction of recently added plugin to zencart based eshop

Dear friends, recently, we have added a new plugin to our zencart based e-shop - CEON Uri mapping. Everything seems to work fine except for 2 problems: 1. (minor) - on ceon uri mapping config page, we´ve got this error: Warning: htmlentities() [[login to view URL]]: charset `windows-1250' not supported, assuming iso-8859-1 in .../includes/classes/[login to view URL] on line 774 2. (major) - after installing this plugin, we can´t provide certain changes in our admin section - we still can add products, change order status, etc, but we can´t change templates, have no control over layout selection, add reward points, etc. obviously, we would like to fix this :-)