to add more stuff just follow step "2" above.
to delete/move stuff within a playlist...
here's a step by step...
1.first navigate to the playlist you wish to edit,
load that playlist(by pressing short select),
then pause(or if you really want to you can keep listening),
2a.make sure you are now on the playback screen know here as the while-playing-screen(wps),
now enter the the "wps" context menu(press long select),
select
Playlist,
select
View Current Playlist,
2b.highlight the song you wish to delete/move(within the
View Current Playlist screen of course) and open its context menu(press long select),
select
remove in the context menu if you wish to delete the song or,
select
move if you wish to move it.
if you choose to move it an arrow/pointer will appear in front of the song you are moving.
if that was not the song you wanted to move then just leave it where it is and press select.
other wise move it to where you want it and press select to confirm its new position.
to move/delete other songs simply repeat step "2a+b",
or if you're all ready at the
View Current Playlist screen you can just do step "2b".
then if you are done or wish to do something else you can press either the rewind or play button to return to the wps and then sub menu if you wish to exit the wps to the main menu.(strangely you cant go back to the wps context menu from here, so if you want to save the changes you've made to your playlist you'll have to go back to the wps first then re-enter the wps context menu)
3.once you have finished editing your playlist and you wish to save it...
first you make sure you are now on the wps,
open its context menu and select
Playlist,
finally you select
Save Current Playlist,
rename it if you wish other wise just press play to overwrite the old one.
note: if you do not save the changes you made will only be withheld until you load a different playlist.
That'll be all.
you can also edit the file itself using the "text editor"...
navigate to the playlist you wish to edit and enter the context menu for that playlist,
select
Open With... and select
text_editordocumentation for the "text editor" is
herenote: i wouldn't suggest using the "text editor" to edit you playlists due to the poor documentation... unless of course you want to try and figure it out.