See, Lexus/Toyota had a little design flaw with their driveshafts, and control arms so it caused the commonly known "clunk". Now think of it this way, at least Toyota tried their best to find a solution (this is like their 5th or 6th attempt, and I've been thru all of those attempts) and they hit the jackpot this time. Other car companies won't even go to this extent to find a fix, especially if it's not a safety issue. So we should all give Lexus credit for trying all these years to finally come up with a permanent fix.
Now as for your sunroof issue, you can fix that yourself. I don't remember what page in the manual it is in, but all you have to do is,
1. Put the sunroof in closed position.
2. Tilt the sunroof open
3. Hold the "tilt" down (even if the window's already tilted) and wait for a few seconds.
4. The moonroof should close half way down
5. Finally, try it.
;)