No, ther isn't. There's just MTX_V60.
Now, I've unistalled completely MyTraffic6 and reinstalled it following the manual. Then I downloaded again the patch "patches600", moved it in C:\MyTraffic Professional folder, put it under the "MyTraffic" folder (not into it), then executed as administrator...and after 10/20 seconds the installation was complete, but still I can't see any changes in the "My Traffic" folder. There's still just one file "MTX_V60" (not MTX_V60a) dating back to 15/05/2015.