I just sent a post that will make absolutely no sense. I have done a screen shot of my MBX where I selected a file from a USB that I would have saved in a folder for my 11000 that could be used in the 10000 and could see the pictures by having the "Preview" selected. Could there be something gone out of your program files that is causing your problem. I'm just making a wild guess with that comment as you are much more knowledgeable about these things than I am. Most definitely Janome should be aware of this problem because if you are experiencing this, there are probably lots of others as well.
Thanks for bringing my attention to this feature as it never occurred to me to use that before for this purpose.
Happy New Year to each of you on the forum. All the best in 2012 for lots of learning and fun.
Cheryl - Saskatoon, Saskatchewan Canada