MC26 /MCC 30002, <optional channel #>
This plays a channel if MC is already started. <optional channel #> is the channel number assigned to a channel (second column in Manage Channels window). If the channel # is not provided, MC plays the last played channel.
Yes TV channels can be put in a playlist. If you check your "Recently Played" or "Recent Playing Now" playlist (if you have one), you will find your channels there. You can drag these channels into a new playlist.