I loaded the beta patch as tech support suggested and deleted the cache registry entries as they also suggested. When I re-imported the offending files I had the same problem with the same images and videos. I gave up on importing those files and finished my video so that I could start another.
Keep in mind here that I started the aforementioned video in PD12, but then upgraded to PD13 mid-stream. It was then that I had the image and video problems.
I started a brand new session in PD13, loading other images and videos. Out of curiosity I decided to see if the previously offending video and image files would load normally into the new session ... et VOILA... they worked just fine.
So, the problem must have had something to do with starting in PD12 and trying to finish in PD13.