I have loaded a heel polar for my boat.  Works fine in the number boxes to indicate the target heel.

Now I want to edit the heel polar in Exp (sail-polars-heel).   I can go to edit mode and it will show me the graphical representation of the polar.  However I only see a few dots representing the stored tests and also these dots are plotted all near the center of the graph (so with a heel of 0-4 degrees) while I expect e.g. an upwind heel of 25 degrees.
Heel is stored in my log files ( I see the correct values being stored in the log file column for heel). When I edit my Nav or Perf polar I see many dots of all the saved tests and here editing these polars works fine.
I have selected to show all tests.

What am I doing wrong or what goes wrong when editing the heel polar?