Connecting the wrong way round can cause damage as pins 41-44 have voltage to power the drive. Although by the sounds of it, there doesnt seem to be any damage to the IDE port but you'll know more when you can test the IDE HD
Was the back of the adaptor protected from shorting out ? Bit of tape to cover it prevents it from shorting on anything metal it rests on.
How about linking to the auction so we can see what you've got.
