During the Open Mic Webcast held in May of 2015, Tony Payne, Senior Software Engineer, spoke on the topic of UIM Client Tracing and provided information on where to find the logs, trace settings and the differences between client versions.
The video is available at the IBM Collaboration Solutions Support YouTube channel:
https://www.youtube.com/watch?v=nP4wwj4VbBg
A full video of the session, presentation slides and audio recording can be found at the Webcast document for this event:
http://www.ibm.com/support/docview.wss?uid=swg27045188