STL360: MP4 publish crashes/freezes at last step of adding audio track

Thank you for the extra info Katie!

My project does not contain any videos, so unfortunately my publishing problem would be caused by something else I suppose. My coworker (who is updated to the latest version of SL360, also on Windows 10) was able to publish the project to mp4 after making a copy of my file, which prompted ME to try making a copy of the Storyline project file and attempting to publish the copy – which worked! Not sure why a copy of the original was able to be published, but the original would not.

We are unable to share our project files, due to containing customers' proprietary information, so I wasn't able to send the Support folks the Storyline project file :(  But opening a copy of the originally developed course allowed the publishing to go through all the way - I have the mp4 output I needed! WHEW!