I am already discharged as a user, but would not have token to compile.
I don't think I asked correctly. I would like to know how to trace the error when it occurs.
Either way, by trial and error I could find out what the problem was.
Attached the image of the panel where I marked Co a red circle the place where I had consigned an icon that did not exist.
Removing that icon, ie leaving it blank, compiled without problems. However, and as a constructive critique, it would be important to be able to know why it gives error to avoid wasting time imagining where the problem might be.