after any update PcDmis gets rid of favorites on home screen and defaults all settings. How can this be avoided during updates??

Export the settings (settings editor) from your current installation prior to installing the new version.
After installation, import the settings you exported (backed up) using the settings editor for the newly installed version.

Or, simply import the settings directly from the old version in the new versions settings editor (not everything may be updated). There is a button for this.