Expect this dispute to drag out for a while. Steve is dead, and the market for mega-yachts is never brisk. If the contract had a high content of handshakes and winks instead of numbers with signatures, the dispute could get uglier than the yacht, and that's saying something.
Nope. It's already been resolved with the family promising to pay the extra 3 million.
Source (Dutch; google translate doesn't handle it well): http://www.nu.nl/internet/2990610/familie-steve-jobs-lost-geschil-rond-boot.html