Apprunner and viewer crash at statup way down deep in nspr at startup writing keys to the registry. it appears to be a memory corruption bug because the system heap is corrupted.
Since I can't do any work until this is fixed, I'll take it.
rjc's checkins to nsCommandLineService.cpp and nsRepository.cpp of today seem to have fixed this problem, and I found the same thing in independent testing. I'm marking this fixed.
Old bug. Mac build works great now. Marking Verified.