How to register a new MP3 player? Why there is a flow for doing so?

To register a MP3/Portable Media Player, insert it on the basestation. When the USB LED is blinking slowly, go to iMorphosis's iManage portal and select add new player.
These steps pair up your portable media player to iManage account so that PodcastLink can recognize new content for the player. Now you can take the player and plug into any basestation and it will update YOUR content.