all the downloads on
www.technicskn7000.com will load into the kn7000 and are in kn7000 format, but those that are in subcategories for the kn2600, kn2400, pr804, pr604, pr54 etc will also load fine into those machines to play the styles and registrations.
Your question was about single composer load, which is page 3 of the load screen. This will only work with the native format of the machine. Thus a kn6000 save will load normally into a kn7000, but if you try a single load it will not work. If you load the kn6000 file and immediately save it on the kn7000 to make it a kn7000 format file, the single load will now work normally from this file.