If this was, as has been reported, an in flight fire and emergency landing, it appears to be very similar to a Fed Ex incident that occurred back in 1996.
In that incident, a DC-10 enroute from Memphis to Boston developed a cargo fire over New York State, and diverted to Stewart Airport in Newburgh, NY. Although I did not realize at the time what was happening, I actually witnessed that flights approach into SWF. His turn onto final was hard and steep, and he was obviously well above normal approach speed. At the time, I wondered what the hell he was doing. I was on a highway about 1/2 mile away from the runway as he passed by. I did not learn till later in the morning what had happened. Almost immediately after touching down and stopping on the runway, the aircraft was consumed by the fire, and the crew had to escape the cockpit via the escape cables.
If this recent incident involved a similar situation, I can see where smoke in the cockpit, causing a high speed approach and touchdown, and exacerbated by the MD11's critical handling characteristics, could result in a hard landing and a resultant landing gear collapse.
fyi, here is the link to the NTSB report on the Newburgh incident. As you read it, you will see that it appears very similar. The biggest difference appears to be that the Fed Ex plane in this case was a DC-10, which is not prone to gear collapse in the way the MD-11 appears to be.
http://www.skybrary.aero/bookshelf/books/373.pdf
The fact that the Lufthansa crew got the bird on the ground and were able to walk away from it shows the level of their skill. Kudos to them. Once the final reports come out, it will be interesting to read how they performed vs. the checklists that are currently in use, to see what changes have been made for in flight fires.
Patrick