DSO Quad - unable to mount on PC


At some point my DSO Quad stopped writing files to internal memory. To fix that, I tried reuploading firmware (v2.72) using this guide. I am using a Linux machine as my Desktop PC.

The important thing is, after I managed to reupload firmware, I also restored internal memory from image file (Dso.img) available from the guide I mentioned above. However, this image file was made from a 2MB version of the DSO Quad, and I have the 8MB one. As the result, DSO Quad has no problem (it seems) writing the files to its internal memory, but I cannot view them from the computer. I get the following error:

Is it possible to reformat internal memory somehow so that I can view files again from the computer? Should it be FAT12 (it’s impossible to format a 8MB disk as FAT16)? Is 8MB internal memory image available for download? Or is there any other solution to this problem?