No events. Front panel only has indicators and controls and the program is not waiting for any input. It runs for a while and then stalls without an obvious reason.
It is admittedly an ugly program with many locals, maybe race conditions ( I don't care, because they only apply to writing stuff into indicators).
What really puzzles me is this strange behavior: flawless operation, then unpredictable stall and going ahead from the last operation whith a mouse click into the front panel. Please note: I don't have to engage a control or something just a click on the grey non-functional surface inside the window.
I can't believe that this is a matter of my code.