I've recently become the proud owner of a 530 having previously used an Etrex 22X.
When I create route on Plotaroute I then save it to downloads, connect and open the 530 to my Mac and drag the GPX file to the courses folder.
On disconnecting the 530 and switching it back on the GPX does not appear under courses, however when I reconnect the Garmin to my Mac and open it the file is there under courses !
What am I doing wrong ?