[darryl]

Cloning an sdcard is trivial from the linux command line with the dd command. The technique is to use dd to clone the whole original sdcard to the new sdcard which must be the same or larger with this particular approach. Cloning the partitions does not work, because it does not capture the space before the first partition, including the boot sector. This is likely what they did wrong. Once on a larger sdcard, the data partition can be safely expanded. Assume, for instance, that you have a Linux machine with the sdcard from the Kobo as /dev/sde and a new 16GB sdcard as /dev/sdf. The command to do the job can be as simple as "dd if=/dev/sde of=/dev/sdf". Of course, specifying an appropriate block size to copy would make things go faster, but the above command basically makes the 16GB sdcard a clone of the 4GB card, and it should boot. Though there is not much point in stopping there. The next step is to expand the size of the appropriate partition to actually use the full 16GB which can be done with any number of graphical and command line tools.

Finally, a caution. If you use dd, you must make sure you are specifying the right input and output disks. It is essentially creating a byte by byte copy of the input file. If you specified your primary hard drive as the output file by mistake, I would not like your chances of recovering much from it.