Problems displaying composer field properly v3.01

[ohrenkino]

What kind of files are we talking about? mp3? wav? something else?
Unless you have created a field mapping from COMPOSER to FILEOWNER (see Tools>Mpeg>Mapping) this is definitely not the normal behaviour and must be down to either user error or some other local configuration like you only labelled a column "Composer" but it shows the field contents of FILEOWNER.

Here is a link to an FAQ topic of how to copy one field to another:

Actions and batch-operations

How to copy one field value to another field? Example how to copy the content of the ARTIST field to the ALBUMARTIST field: Create a new action in an existing action group or make a new action group. Action type: Format value Field: ALBUMARTIST Format string: %artist% Note: If you want to copy all possible values of a field (in case you have multiple artist fields), the internal scripting function $meta_sep can be used in the format string, e.g., $meta_sep(artist,\\\\)