in my model, a method inserts the entity name in a tablefile.
When the entity leaves the model, the name in tablefile becomes (?)
Is there a way to tell the software to not do this, without converting the object in string?
It's normal. The column shows the MUs name so when the the MUs disparee because you delete it or if you reset your model, it shows a VOID.
You can change your column format from object to string. (Select your column Click right -> Format -> string).
and When you fill your table convert the MU to a string thanks to " to_str()" .
Table[4,i] := to_str(@) ;