I agree that the behaviour of the timer and such is not ideal. However I don't think we've never intended the timer to be something which indicates that the app is working and hasn't frozen/crashed, it's basically just a convenience to let you know how long the render has been going. Of course we also understand that people do think that the timer is something more than we intended it to be, so at some point we will need to make sure it keeps running as long as TG2 is still working.
Just because a program isn't responding doesn't mean it has frozen. Generally speaking the OS decides a program isn't responding if it has stopped processing events sent to it by the OS for a certain time. The program may however just be really busy calculating something and not looking at the events being sent to it. Mac OS X displays a this colourful spinning cursor when an app stops responding. People call it the "spinning beachball of death" or similar because they think when it appears a program has frozen. With one of the OS X updates Apple changed the time before this cursor came to something much shorter than it had been, and it triggered a whole lot of complaints from users about apps which were freezing up. They weren't and they were working just as well as they had before. I think the reason for Apple shortening the time was to force developers to rearrange their apps so they checked user events more frequently and perhaps move calculation intensive code out into threads running separately from the UI thread. Often that's easier said than done though. This wasn't really a bad thing ( just sneaky and problematic for developers ), because more responsive apps are better and often make working with multiple apps at once better.
It would be better if TG2 didn't do this, of course. The reason the timer isn't updating is probably because the app isn't processing events, which means it isn't redrawing the UI as well as making the OS think it has frozen.
Regards,
Jo