.......and after wasting 3+ hours of my life...:(
Tried using the stick on my sister's laptop and everything works fine. Copies / reads all types of files without any problems !!! ( mine is XP, hers Vista ? )
Guess it must just be my PC for some reason, not correctly recognising something about the stick / USB connection ?
My loss - Her gain !! - And I suppose another £5 to eBay for a replacement
Thanks anyway for your efforts.