What version of Timeslips? Since I do not know your version a way that works for all versions of Timeslips is to browse to the Loclinst folder on the server using the UNC path, and then run setup.exe.  

Running 2016. Tried install via the UNC path and the software looks for Disc1 BIN file. Extracted the setup file, which allowed for the installation via UNC path. Install completed, but TS looking for CFG file which is on a mapped drive. I changed the path in the registry, but it defaults back to the mapped drive. Y:DataShare\Timesplips instead of \\xx\Datashare\timeslips

Sounds like something is not setup correctly or you are not starting from the correct path. In Timeslips 2016, on the workstation, you can go to Station Administrator and change the install path to the UNC path but I suspect you may continue to have issues if you are not properly setup on the server. 

Have had 10 or so users working fine, up until I added a new workstation. I have tried to add the UNC path via the station manager, but it only allows me to browse via the mapped drive path. Am I missing something on the station manager?

You don't HAVE to browse for the UNC path, you can type it in.  But it sounds more like a Windows permissions issue right now.  See if you can type the \\xx\Datashare\timeslips path in instead of browsing.

Nancy Duhon, Esq.
Duhon Technology Solutions, LLC
Master Certified Consultant for Sage Timeslips
Providing individual Consultations and Third Party Remote Desktop Support - including older/unsupported versions.
404-325-9779
[email protected]

I have tried to copy and paste or just type it in with no success. Maybe I need to run the station manager as admin?

Change the Install Path in this key - that will make it stick

Computer\HKEY_CURRENT_USER\Software\Sage\Timeslips\v24BDE\General

I tried the darn registry key entry as well, but keeps reverting back to the y:timeslips. Strange behavior indeed.

Try disconnecting that mapped drive.  It sounds like that computer or user profile in Windows has much bigger issues than just this.