Limit access of transition states of a work item to roles

If you are the workitem creator, you can do everything you want. For others, only those have the roles can perform certain state transition.

Permission to trigger workflow action is not working

I am currently using RTC Standard edition.

How do you limit transition of states of a work item to only users that are part of a certain role. For example only TeamLead roles can transition a work item from Submit to Assess.

In the Process Configration Tab:

Team Configration->permissions
WorkItems->Trigger a workflow action

You will see all the states of a work item. For assess state I have only checked the TeamLead role but any user can still transition the state from Submitted to Assess. I also unchecked all the boxes for all the states which means that no user should be able to transition the state of any workitem. But that is not the case, any user can still transition to anystate. Am I missing something here? Any thoughts.

Is this a bug in RTC?

Thanks!
-Arnold