I removed the ebooks application again and did a soft boot on the system.
The PRS+ firmware is loaded and is working correctly.
I was able to use Calibre to download 4 books to the PRS-300 and was able to read everything ok.
So I have an ereader that works, but I would love to have the ability to scale fonts.
Any ideas on what to do next to try to get the ebooks application to work?