Hello @David_McCartin ,
Are the images of your PDF only not showing when you upload them into our system? We've heard of this issue sporadically popping up for some customers, but with no consistency as far as source of the pdf, size, etc.
Generally, compressing your PDF or re-converting it to a PDF in whatever program was used to build it has been able to resolve the issue. However if it continues to be an issue, our support teams may need to look at the raw file on its own. Additionally, you could use a 3rd party drive to host it in, to see if it also has issues with displaying the images after upload, or if it allows them through.