I have another interesting data point and a solution that worked for me.  It turns out that not only was the export not showing the image, when someone else was looking at the diagram in Lucid they also got a blank square.  Object acted completely normal on my side.  I ended up deleting the object and inserting the image again from the menu (rather than pasting it in) and it resolved the issue.  

Hi @wlaforest, thank you for posting in the community. I’m glad to hear that removing and reinserting the image helped resolve the issue! 

If you or any other user reading this run into image issues, I recommend checking out the following Help Center article for some steps that you can try:

• Troubleshooting: Images

If those steps don’t help resolve the issue, please feel free to reach out to our team and we’ll be happy to help troubleshoot. Cheers!