Talking to Mike in their user support (he does not work for them), his inclination was RUN to get off 2.5, they had not fixed everything on 2.8, but it was ooddles better to work from.
He also shared that clearing just the PHOTO gets rid of the flashing in the visualizer and it's a bug still in 2.8, but you can clear that by going into configuration and hitting clear in the load photo screen and said that makes it go away, but leaves your models intact. You might try that from time to time.
I have less issue with that than I did, and I am trying to clean up extra timing marks whenever I find them as well as just a general rule.