The pushModeLeft fails after entering the playlist name. It still refers to old mode names. 
Probably should be 7.0

fix is: 
Index: server/Slim/Plugin/SavePlaylist/Plugin.pm
===================================================================
--- server/Slim/Plugin/SavePlaylist/Plugin.pm	(revision 16763)
+++ server/Slim/Plugin/SavePlaylist/Plugin.pm	(working copy)
@@ -149,7 +149,7 @@
 	if ($type eq 'nextChar') {
 
 		# re-enter plugin with the new playlist title to get the confirmation screen for saving the playlist.
-		Slim::Buttons::Common::pushModeLeft($client,'PLUGIN.SavePlaylist', {
+		Slim::Buttons::Common::pushModeLeft($client,'Slim::Plugin::SavePlaylist::Plugin', {
 			'playlist' => $context{$client},
 		});