Thanks for your quick reply, Alec.
I tried this through card reader before but did not succeed.
This is what I did:
I copied the complete content (about 80MB) of the 128 MB card by dragging and dropping 'Private' directory to PC. After that I deleted all TFLD folders containing files that I do not want to copy so only folders that contain songs remain. After that I copied 'Private' to new 64MB card. After checking that card in KN7 it shows empty content.
I will give it another try tonight.
Bert