[Typo3-dev] Chaging the way a record is listed in the backend

[Martin-Pierre Frenette]

I am currently working on an extension, in which some of the records
are MM records between 2 tables.

These MM records however, have specific information, so I want them
listed in the backend.

I have chosen which field I want to list them on, but it is a database 
relation field.

However, instead of listing the name of the related record, it shows the
UID of the linked record.

I know that with foreign_table I can adjust the display, but nothing 
seems to work.

Even more odd, when I change the diaply icon to an invalid record, the 
old icon is still displayed.

I did clear all cache...