Apparently they have changed the UI a littler bit. There used to be a "DNA" link up on the top of the page (menu bar), but now it has been moved into "View". Move your mouse cursor onto "View", you will see the options, such as "PDF/PS", "DNA", "Ensembl" etc, which were in the menu bar before. Click on "DNA", it will give your options to download a segment of the genome of your choice. Good luck!