There are a couple of intentional exceptions:
JAZZ FILES For Jazz files, the title refers largely to the name of the arranger. The name of the composer may be listed in the text of the file.
SYMPHONIC CHOIR This section is essentially vocal in nature, but has been set aside separately from the Vocal Section in the library and organized differently for various reasons mentioned in this link. While the title still indicates the composer or arranger, the order of files is not alphabetically ordered by composer, but rather alphabetically by the title of the work.
Use of the search engine can alleviate any complications due to these exceptions.