The WTS folder under each users "Z" drive is for WTS personal settings and the Desktop is part of the profile that gets loaded/unloaded every time one logs on/off.  We strongly recommend users not to save files in your WTS desktop (which saves to the WTS folder) as things can become unstable.  The best practice is to save files in a folder created at the top level of the "Z" drive other than the WTS directory.