Bill, go to Help>Troubleshooting Information>"Refresh TenFourFox…". Follow the steps on screen.
Make sure you're not using an old Firefox version on the same computer, this may destroy TenFourFox's database for bookmarks and history.
Then open Safari, export your bookmarks to HTML. In TFF, you can then click Bookmarks>Show all bookmarks, click the Star Button and choose Import bookmarks from HTML. It may take a while until the import is finished (up to several minutes if you have a lot of bookmarks to import).