BACK UP YOUR SETTINGS BEFORE DOING ANYTHING ELSE
If that's the case, you're probably running Chrome (or Safari) and have a corrupt user profile, and/or something else preventing RES from saving settings / data. This is usually solved by uninstalling RES, closing all instances of Chrome to ensure it closes completely, then starting Chrome and reinstalling RES.
A few users have reported the above solution not working, but reinstalling Chrome did fix the issue in their case.
This is a huge release with a ton of changes that are not all listed here. We're working on a better way to automate our changelog because so much work is getting done! If you contributed something and weren't listed or credited here, please feel free to let me know on reddit (message /u/honestbleeps) and I'll update the page!