Raised and answered, but quite a long time ago.
There is a file in your map folder called mapsettings.cfg. Among
other things, it contains your favorites. If you pull that file over to your PC and use a tool like POIEdit, you can remove the 'dross' (the "other things") from the content of that file and wind up with just your favorites information. Then you can use POIEdit to save that as an *.ov2 file (a TomTom POI file).
Having done that, the MyDrive web interface that is used to work with the content of your Start 52 can be used to move the *.ov2 file from your PC to your Start 52.
I call my file _Favorites.ov2 (yes, with an underscore) to keep that file at the top of the list on my newer TomTom units.
The app can be dowloaded here >>
http://www.poiedit.com/downloads.htm
It will directly open the mapsettings.cfg file, and as I say, can be used to edit out the non-favorite information from that file, then save it to your PC as _Favorites.ov2.
Once you've done that, the web site at TomTom for communicating with your Start 52 is
https://mydrive.tomtom.com/en_us/ if you can work in English, or you can click on the map to change to whatever language you prefer.
You set up an account there for your Start 52 (if you haven't done all of that already) and use that web page to transfer the *.ov2 file. If you need help at that point, just ask.
Long ago, there used to be a utility that did most of this for you, but that TomTom utility hasn't, as I recall, worked for quite some time due to changes in the interface of newer units.