Have managed to install for one user, but had to disable Outlook add-in as it meant the user couldn't search in Outlook while they were on a call and even after the call was complete - they had to restart Outlook to rectify.
For the other user I couldn't get it installed at all - got the ccSIPoid.dll is missing error although they were using Outlook 2010. (I've seen above users with this issue on Outlook 2013).