From some days I have this problem in my garmin 840.
Last course Added is a "ghost activiti" and I can't delete...
Could you help me. I have updated my device and the problem doesn't dissapiear.
thank you Best Regard.

The last course glance I believe is something cached in memory when it imports a course. Those values are bad and maybe a course imported failed.
I think the easiest way to fix it is to send over a new course so that Edge processes it and updates that information memory.