Hello,
afaik, there should be no issues regarding this functionality.
The latest version is 2.3.3. However, most likely, the problem will be elsewhere - maybe some other component / mambot is rewriting the values set by JoomSEF.
I would try unpublishing other mambots that could be causing this. (any of the non-default ones)
Also, make sure that AFTER you changed the configuration setting, you cleared all tha caches, but as your tried reinstall that should not be problem either -- so just to be sure.