If a release on MB has no release types set at all (as of time of writing e.g. https://musicbrainz.org/release/af96cd94-f759-4f9f-8c63-75404d4853dc has), then Picard applies a score of 0 to the releasetype. This leads to extremely low scoring.

Instead it should use the default score defined for "Other", as it already does for unknown types.