The things important are:

1. Checkpoints continue to be logged (you can see the last one and the time since in the task properties in BOINC Manager).
2. The CPU time in that same view continues to increase relative to the elapsed time. If Elapsed time goes up and CPU time does not, that's an indication of a locked up task. If both go up quasi in sync, things are 99.99% of the times fine.
3. The progress percent continues to go up. Some do this is fixed percent steps, others do this smoothly, but noting that progress % is relative. It can go backwards if the task hits a harder section to compute for then BOINC will assume that the remainder is also harder. You'd see the Time to Complete go up at the same time, rather than going down.

When a task uploads and reaches a status on return other than "Error", and do not end in "Invalid" after verification, things are fine. HFCC is a very well established application. We've done 8 targets with success, 60 million results. Why would with target 9 and the exact same compound library, processing be problematic?

--//--

I took my P4 off this project because completion time was approaching 60 hours. It's back on c4cw for now.