How to troubleshoot export issue on Mac running Virb Edit version 5.4.3 (180910.1208)

Hi, new guy here, used Virb Edit years ago but never really done anything with it other than just play my videos.  

I'm able to import my video fine and then add the fit file for overlays, but when I try to export, no dice.  I see it tries to create a folder but that fails and I get a generic error.  The  video export has been aborted.  

The video is 4k / 60 FPS, tried this at these setting and also lowering it - no change.  Tried moving it to different spots on the Mac, no difference.  

Saw there were suggestions to another similar post about muting the sound - no change.  Exited the software and went back in and then imported video and then immediately tried to export - same problem.  

Anyone have a suggestion I can try?  Didn't see patches or a different version, but maybe there's something else to do / try?

thanks!

Chris