Furthermore (I don't know whether it is related to the above topic, but something else is odd.
As the file was not moved to the right folder on the disk, I did it manually (right click/edit/rename, by using the target folder and no pattern).
Result is:
- the file has been moved correctly on the disk
- but the podcast entry in MB still points to the original file location (where the file is absent, of course).
Thanks