Been working on this project for nearly 2 months. 17 different videos. Each of the 17 videos has its own Library/Event settings and locations.
Exporting directly out of FCPX using Sharing. I've exported over 50 videos before having the issues of exporting. Plenty of hard drive space. Loads of memory. All stats are below. The exports all stop at 91%. It doesn't matter which ones I am trying to export now, they all stop at 91%. I then have to cancel them; and also restart FCPX as the progress circle above is frozen at the 91%.
With a few good results I have been able to export 2 additional videos by first deleting ALL the Render Files within the Generated Library Files within the Library, as well as deleting ALL the Render Files within the Generated Event Files. Sometimes afterwards however the timeline will not render. So will need to restart the computer. I am starting to hit a wall here and am really baffled as to how I will troubleshoot moving forward.
I also tried using Compressor but Compressor also did not move forward.
All of this seemed to have started to occur after receiving 3 png files and a jpg to include in one of the timelines.
Then make sure you have the latest Pro Video Formats loaded. Starting with Mojave that is in System Preferences>Software Update.
If this doesn't help any, state your camera codec inc'l resolution, and what codec you are exporting to. Disable background rendering : Final Cut Pro>Preferences>Playback>Background render (deselect).
If not already done, define an external location for cache. This is on a per library basis. Select library in left side bar. In library inspector at upper right, pick Storage Locations>Modify Settings. A popup dialog will ask "Do you want to move your render files?" You answer "don't include". This creates a new cache file location, discards the old ones, plus gives you the subsequent ability to easily delete the cache files by deleting that folder's contents using Finder. That is safe, and useful in situations where we suspect a possible cache problem.
Then manually select all clips in a timeline via CMD+A, then CTRL+R to render them. Examine if the render completes or gets hung. If it hangs note the location. If it completes try to export that as a ProRes file: File>Share>Master File, Format: Video & Audio, Codec: ProRes 422. If that works try another timeline or library using the same method. If it fails, state the specifics. If they all work, try exporting to your preferred output codec.