Your player will reach out to the cloud periodically for changes, so when you make a change in the manager app, it will usually take 1-10 minutes for the changes to appear on your player depending on the length of the playlist.  You can force pending changes to happen immediately simply by rebooting your player (tip: if you're using a XOGO Mini, you can reboot the player from XOGO Manager under Players -> (Player Name) -> Advanced).