AFAIK, it just takes way longer to update Sync if your unit is several updates behind, as in hours, but it does work. Have to look into non-MFT Sync, that might be the issue right there, bpd updated the software in his '10 SHO, so something should be possible for the '12 MKS also.
BTW, can you list the 3 files you put on the USB drive?