Mountain Lion doesn't accept DSC RX100 AVCHD files

I watched the instructional videos on Sony's website which were made using OSX 10.7 and obviously no longer apply. When I try to open the "Private' folder in the finder, it will let me play the files, but not download them. In iMovie, it shows the number of files, but not the images, and it won't import them. Trying to open that folder crashed Final Cut Pro.

Someone here mentioned Adobe Premiere Elements 11, but is that really the only option?