If there's HR data in the track you are selected (it's OK if the location has them as files -- that's where TF gets the data) it should prompt you to save it as a TCX.
For some reason it isn't seeing it. Are you sure the track you are picking actually has HR data and isn't another track without it?
Otherwise, maybe send me the Current.gpx file. I can mock up a fake USB storage and test it on my end.
Well, just to be as accurate as possible, I stopped the track recording, cleared the track log, set the recording interval to 1 second, started the track recording, went for a short walk, and then stopped the track recording.
Voila. It seems to be working as it should. Yes, TCX does come up as the default option for the first segment chosen. I used TF to save both a GPX and a TCX. They appear to have identical information, including heart rate.
But here's a tidbit that at least makes the "problem" reproducible.
I have always been in the habit of just leaving the track log on (with my older units) and that has never been a problem. It was on when I first encountered the "no HR" problem I described for the Oregon.
When it is on, the source column in the merge/delete dialog shows "active Log" and not a file location. The same segment in the (presently very limited) active saves via TF
with HR when the track log is OFF, but without HR if the track log is on.
So I don't know whether I have just uncovered a "bug," a "feature" or just an annoying idiosyncrasy. But I expect it could have a software developer pulling his hair out (or just muttering under his breath).
KenF