Adobe Premiere Rush Not Exporting Correctly - Wasted my Free Exports

I'm using the latest version of Adobe Premiere Rush.  I imported multiple video clips to create a video project that is almost 28 minutes long.  Everything looks great when I preview it.  I exported to my local disk.  Everything looked ok until I tried to view the video.  The first 17 minutes are great and then it makes a weird noise and the video and sound freeze.  If I try to scroll to the end of the video, it resets to the beginning, but says it's at a later time in the video.  I tried another export after reading a suggestion to lock all of the tracks.  This time there was no sound whatsoever.  This wasted two of my three free exports.  I just tried one last time.  I unlocked the tracks again and this time tried to export to YouTube and chose the save a local copy box.  After waiting for over 20 minutes for it to render, it says it completed.  However, it did not appear in the local folder I selected OR in my YouTube account.  I need this video for an event tomorrow night!  This is a big problem.  I was really loving the software and had grand plans for my second two free exports.  Now not only are my free exports gone on my first project, but I don't even have a usable copy of my project.  Very disappointing.  Please help!