Thanks for trying this out and reporting the issues. I originally had it only countdown and the stop at 00:00. However ,yesterday I added a feature that it would start counting up afterwards, so that one could see the amount of the overtime. But I obviously did not think of my "clever" Continue feature, so they are not working nicely together. What I'm going to do now, is that I will restrict the Continue feature only for countdown. This should also fix the strange minus signs.