If the above doesn't help, try adding a WAF exception for com_jce, as described in the documentation's example. In fact, that feature was developed in cooperation with JCE's author in order to work around some issues with front-end editing.
Regarding the tickets, what kind of error do you get? I can see that you have full permissions for the ticket system. Other users with the same permissions were able to submit tickets. If you give me the exact error message I might be able to find out what is going on.
Nicholas K. Dionysopoulos
Lead Developer and Director
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