A doubt:

How can I copy specific fields in Tags from a files to others, for example to copy only "Titles" from a number of files to other files...

Thanks

This will work only via the export function with which you export specified data and then can re-import it with a similar mechanism.
It depends on your export mask which data will be found in the export file, e.g.
%artist%;%album%;%title%
you may then import only the title with this mask:
%dummy%;%dummy%;%title%

Copy&Paste via clipboard always transfers the whole set of fields.

See there ...
http://forums.mp3tag.de/index.php?showtopic=6373

DD.20120504.0644.CEST

OK. I get it. Thank you
Time to get some practice with the issue...