I do understand now that vp_..... are view parameters. I do not know how to get this accepted in the sql query for the view definition because currently it is seen as a database column.
Assuming this seems quite a standard action (setting up multi-lingual) and the set-up procedure as described in the developers guide should work, I must be overlooking something obvious but I do not know what it is.

I hope somebody can give me a direction.

Regards,
Paul