System output Task Executing not working on OmniCore.

I discovered possible bug in RW 7.1 - system output "Task Executing" is not coming active, while task is actually executing. I have used this signal to monitor robot tasks statuses from PLC with earlier RW 6.xx versions and it was working perfectly.
To eliminate possible other mess ups in configuration, I created in simulator two totally new systems with minimal configurations - one with RW 6.11, other with RW 7.1.
Result is still same: working with 6 but not with 7.

Any ideas? Is there a bug or should it be configured differently?