Undoubtedly my carelessness, but I have gone over the procedure several times, and can't spot my errors.
OK, tried several more times, and still no site styles. Final result is third image. Error message pops up at most stages.
I've had that error, too. The fix is quite easy:
Use a database admin tool like phpMyAdmin and delete all tables related to the "KFM"-filemanager.
Be sure to make backups of these tables before deleting them, in case something goes wrong.
All the tables have a naming convention like "kfm_something_somthingelse".
Then apply the new "HTML Editor 3" to your form page. Preview your form page in the browser. When using the filemanager for the first time, you will be asked to reload the page to have tha database refreshed. At that point all the necessary "kfm" database tables will be created and everything should now work.