Hello Elizabeth,
I tried doing this a few years ago because I liked the earlier versions of sounds and rhythms but it wasn't possible. I think the reason given was that some of the settings were not recognised by the latest keyboard and those that the keyboard did acknowledge were immediately updated to the latest format so the moment you saved these settings they were saved in the current format.
However, Fran gave good advice when she gave you Technics website on which all back formats were offered as free downloads but again, some are better than others. Also I am note sure whether this site has closed or the offer of freebies been withdrawn as I thought there was to be a 'cut off' time.
I eventually bought the SD 128mg card from Technote which has all the older keyboards rhythms, sounds and Custom styles on it, but you must be aware that the Custom Styles and the 'ALL' loading facilities didn't appear until the KN5000 I think it was,therefore some of these older styles etc., do not offer these facilties but I can thoroughly recommend this SD card. The full list shown on the Technics site are on it. For your information Technote's website is:-
www.technote.com and their email address is:-
enquiries@technote.com
Hope this helps.
Aud