I uninstalled version 5.4.0 and then installed version 6.0b3, using the link  
http://www.slimdevices.com/downloads/nightly/latest/6.0/

I then went into Behavior within Server Settings and made sure that it is set 
to DON�T INCLUDE COMPOSER etc IN ARTISTS. Then I went into Performance within 
Server Setting and clicked on Wipe Cache.  It then rescanned my music 
database, but after all this it is still including Composers within artists.

Here is an example.  I have an album by Diana Krall � The Girl In The Other 
Room.  Five of the songs are written by Elvis Costello.  If I search for Diana 
Krall it lists both Diana Krall and Diana Krall/Elvis Costello.  If I select 
Diana Krall and then select the album The Girl In The Other Room it lists all 
the tracks on the album.  If I select Diana Krall/Elvis Costello it lists the 
album The Girl In The Other Room which then contains the 5 tracks wriiten by 
Elvis Costello!!  With this example it should only list Diana Krall and there 
should be no reference to Elvis Costello, except in the Composer field.

I notice a similar bug was raised Bugzilla Bug 914, but the problem still 
appears to be in version 6.0b3.

If you need any more information, please let me know.