Hi Darren
So I am back. I changed the config - Opensef Components - Gallery-> Use Alias -> gallery (gallery is the name of the alias)
Then copied your sef_ext.php to compnents/com_zoom. Turned on the opensef and tried, but it still fails to use the mediamanger on the frontend

Please see this topic for them media manager. This is a zOOm Gallery bug:
http://llamacouncil.org/component/option,com_smf/Itemid,55/topic,42.0In this topic there is a link to the zOOm bug tracker. If you would like go over to the bug tracker and confirm my bug and the fix if it works for you. Hopefully zOOm will fix the rest of the OpenSEF bugs.
Then I turned the opensef off - working again....
Information: I copied your sef_ext.php (without changes) on my webserver under opensef 2.0.0.-RC5_SP2 -> you wrote that this combination will not work... did you made some changes on a new sef_ext.php

Bjoern

OpenSEF RC5 sp2 is fine. I had to make changes to my extension for it to work.
Please note that zOOm Gallery is a Release Candidate and my extension is Alpha. There will be bugs. I will do my best to make changes for them both.
Thanks,
Darren