4.7 playlists are stored in the database, so any created in 4.7 will be lost on reverting.
Old 4.6 playlists should still be where you left them even if you imported them (which I couldn't achieve)
Users and settings are stored in the db\subsonic.script file. I reverted back on my main server np but I did backup
my 4.6 db folder first before upgrading - did you
I do not know if the 4.7 subsonic.script file is backward compatible with 4.6 but there is only one way to find out
