The latest version of DipTrace (July 2014) has a completely different library structure.
It is MUCH better than the previous version
Remember, everytime you install a new version, choose a different directory so you don't install on top of your old version.
If you did install it over you old version (& your private library was under the DipTrace directory), hopefully you created a Windows Restore Point. If you did, you can roll back to the time before your new DipTrace install. Now move your private library to a new directory, then reinstall the new version of DipTrace.