Hey Greg,
Well before I did your test, I did a format to the nav directories. I am running the most current update. I turned it on, got a GPS fix and did a screen capture in the sonar/chart view and a side imaging view. Both captures were successful and waypoints were created (blue dots). I confirmed they were on the SD card as well. Hopefully this was just a glitch with the existing data on the card. Will try it out on the water this weekend. Looks like I'm going to have to start managing my nav data regularly on the PC and keep backups.
Will report back if it continues. Thanks!