The washer stopped with Technical Fault F 53

I restarted it, and noticed the drum seemed to be off-axis: Miele W 4840 Technical fault F 53 - YouTube (http://www.youtube.com/watch?v=3j3CCUb4syI)

When I took that load out, it seemed like the drum fell down a little farther inside the machine.

It seems like they've told their technicians that it's a known issue: http://www.mieleservice.com/techservice_residential_pdf/Announce_KDI/SB_FLANGE.PDF

How do I repair it?

I will assume you are out of warranty. I would contact the company customer service desk, explain your issue, explain the tech service bulletin and tell them how disappointed you are in the machine, blah, blah and see if they can help you. In some case they will repair or give you the repair parts. I see far too many front load washer issues and will not buy one.

Many of the front loaders have been built with aluminum pulleys at the rear of the drum which causes a galvanic reaction (It makes a battery out of your machine with the aluminum being the negative pole and the stainless steel drum the positive.). This galvanic action quickly corrodes the aluminum unless a sacrificial metal more reactive that the aluminum is attached to a part in electrical contact with the drum. Here is a video on a machine made the same way with identical parts: https://dl.dropboxusercontent.com/u/8010163/Whirlpool%20Duet%20Washer%20disintegrates%20-%204%20years%20old.flv Here are some charts explaining what I said: https://dl.dropboxusercontent.com/u/8010163/Activity_Series_Chart.png
https://dl.dropboxusercontent.com/u/8010163/chem_6.gif
https://dl.dropboxusercontent.com/u/8010163/ActivitySeries.jpg

Many of the front loaders have been built with aluminum pulleys at the rear of the drum which causes a galvanic reaction (It makes a battery out of your machine with the aluminum being the negative pole and the stainless steel drum the positive.). This galvanic action quickly corrodes the aluminum unless a sacrificial metal more reactive that the aluminum is attached to a part in electrical contact with the drum. Here is a video on a machine made the same way with identical parts: https://dl.dropboxusercontent.com/u/8010163/Whirlpool%20Duet%20Washer%20disintegrates%20-%204%20years%20old.flv

Here are some charts explaining what I said:https://dl.dropboxusercontent.com/u/8010163/Activity_Series_Chart.png
https://dl.dropboxusercontent.com/u/8010163/chem_6.gif
https://dl.dropboxusercontent.com/u/8010163/ActivitySeries.jpg