I am not able to reproduce using Power CMS Builder form Design Extender 1.1.1 with Security Assist from Data Bridge 1.1.3,
Before installing Design Extender 1.1.1, did you uninstall any previous versions that may have been installed?
Did you have any of the other webAssist Extensions installed?
Make sure that you have deleted the cache file from the users configuration folder:
in design extender 1.0.7, Power CMS Builder was updated to use the current security assist version to prevent this conflict.