HELP!@! (I'm backed up, so it's not that.) I did the update, but now my SK-1 thinks it's an SK-2 (judging by the start-up splash screen phrase) - and SPLIT and Manual Bass don't work - probably related. I tried reinitializing by powering up and holding RECORD. Tried reloading my WHOLE setup. Nothing has changed this. I am now reloading the Japanese update zip file from your link, although I downloaded what appeared to be the correct release from the HammondOrgan.com Support link. HELP!
I tried reinitializing the USB (SansDisk) in the SK1 (which thinks it's an SK2.)
Another clue that it's got this identity crisis, is that instead of SET SPLIT POINT, it has LOWER to PEDAL in its place, which p108 of the Manual says is only SK2.