There is another bit of functionality that I added because I could. We will see if anyone uses it.
(copied from post #1)
5) [0.7.36] Ability to make special 'all-books' collections sorted by an arbitrary column. Using this feature, you can make all-books collections sorted by any calibre metadata field, such as published date, publisher, or any custom column. To create such a collection, add 'abs:name' into the collections box in device customization. The 'abs' means 'all by something'. The 'name' is the collection name. If the name is a metadata column key (including custom columns), then you are done. If the name is not a key, then you must add the sorting column information to the sony_collection_sorting_rules tweak.