I can think of two ways to accomplish what you want:
1. Put the category in front and (possibly) remove the category label for everything except series. Use .Reihe as the category label for series. You don't say where genre comes from, but assuming that genre is a custom column, something like:
Code:
sony_collection_name_template = '{category:||: }{value} '
sony_collection_renaming_rules = {'series':'.Reihe', '#genre':''}
2. Create a composite custom column that adds the period in front of the series name, then create your series collections from that. The template for the column would be something like {series:|.|}