Garmin 705 - help downloading routes

[Stick on a Giant]

I've splashed the cash, and so far it looks good. Only problem is trying to download routes from BikeRouteToaster - they come across to the Garmin entitled 'course.gpx', which means whenever I load a new route it overwrites the existing one. How can I get around this?

Also, one route keeps showing as 'error on page' when I try to download to the GPS. Is there a limit on the number of trackpoints I can use on a route for it to download?

Cheers