I use TaskCoach for tracking my daily work for some years now. Lately I installed version 1.4.2 and noticed that I suffer from performance issues with this. I tried older versions and found that all 1.4.x versions (for windows) suffer from the same problem, 1.3.41 is clean.
Whenever I edit effort via effort window, TaskCoach is stuck and unresponsive for some seconds to minutes. After some time it recovers and I can continue editing. Following actions may cause this freeze: edit hour or minute of start or stop time, use buttons "Start tracking from last stop time" or "Stop tracking now".
Deleting effort entries from 3 month caused a 15 minutes freeze.
I suppose it comes from my huge file, 4900 hours tracked, 5975 effort entries total. I was not able to reproduce the problem with a small/new file.
with attached task file it is possible to reproduce the behaviour - just try to edit any effort (or add a new one)