I managed to make a mistake in the previously release of Todour. A mistake that would have embarrased me a bit if I still would have programmed for a living, but I don't and referencing out of bounds on a vector isn't that bad for an amateur. So I've fixed it and now it should work ok.
Qt behaved intrestingly here. Using the exact same input data, program code and Qt build, the program would crash on Windows but mostly not on Mac. Strange. The bug was definetly there and the program should have crashed but on the mac it just carried on. How can that be?