I've tried numerous times to select a different style through Preferences -> Styles, but I cannot seem to get it to work. I have both checked "Save as default preferences" and made sure that I click "Save Changes" in the preferences screen, but it will never apply the changes. I am able to successfully change the parameters within "Regular analysis style [analysis.sty]" however. Unless I am missing something ....
When you're creating a new map, verify that you're changing the map color style as well. If that isn't the issue, then you may want to delete the styles that aren't working and create new ones in their place.