You can rescan just a single folder you've modified (browse to that folder in Location or Folders node and press Ins key). If you want it automatically you can set folders to monitor and set them 'At Startup' and 'Continuous' mode.
You're right. Thanks ... will be fixed in next build.
re title: you can define it directly or using method (same for visible, disabled and some more properties) ... to get the value from such a property we're using our method resolveToValue ... you can check mminit.js for that method and usage.
ad 2) as a workaround you can pin that playlist (right-click on it and choose Pin command) and you'll see your playlist at Home view or under Pinned node in media tree ... this way you can pin almost every object (artist, album, track, genre, folder etc.).
You can pin your favorite albums, artists, genres, folders and have them always accessible from media tree (under pinned node), in home view or in collection view (Music, TV etc.). Just right-click on item you want to pin and use 'Pin' command from popup menu.