Looks like the message was cut off, it should read -215. The error indicates that it's trying to get the head item out of a track group, but the track group is empty. That's a pretty weird situation. Do you have some clips that you've manually grouped together?
none that I know of, I think I know what I was doing wrong now, I was trying to drag elements from timeline onto another instead of copy/pasting them.
Thanks anyways Wil.