The issue.
So the issue is that if you just create a 404.html page and add the line ErrorDocument 404 /404.html to the htaccess file, then when the user arrives at your 404 page all the links to your css files and javascript files in your page are broken, and you are unable to present the page as you'd expect.
So the workaround.
Send the user to a custom 404.html page as you should normally, but as you are unable to make this page pretty, then bounce them straight onto your pretty page (404redirected.html).
Here we go :
Create 2 new pages in your RW project.
Here are the general settings for the 404.html page:
