Whoops, screwed that up - let me try again:
I found this topic:
but not until after I ran into the problem just following the instructions. The instructions note that SD library 1.1.1 must be used, but fail to mention that SdFat library 1.1.4 must be used. Any version higher than that and it starts to throw warnings. Once you get up to the default version 2.1.2, it flat-out gets an error in host_due.cpp (File::getSFN() doesn't exist).
When you get a chance Chris, the applicable paragraph should read:
Click Sketch > Include Library > Manage Libraries... In the search box, enter "DueFlashStorage", select the library, and click Install. Search for the SD library (by SparkFun) and install version 1.1.1 (the default version has a problem with the Altair-Duino). Search for SdFat by Bill Greiman and install version 1.1.4 (the default version has a problem with Altair-Duino).