Fix duration computation for potential NILage of the END by making it always compute by current time on a running task, compute by end if available, and return NIL otherwise.
Fix duration computation for potential NILage of the END by making it always compute by current time on a running task, compute by end if available, and return NIL otherwise.

Shinmera/autobuild,Shinmera/autobuild,Shinmera/autobuild