Hey,
Can someone explain to me the USB protocol side of ISO keyboards?

Here's what I don't understand.
According to specification, the key in the notch of the Return key (#~ on the UK keyboard) is 0x32, and the key next to Left Shift is 0x64.
0x32 is supposed to be interpreted the same as 0x31 (backslash key) on US layouts. However, when I was experimenting with scan codes, OSX didn't seem to register any keypress on 0x32, and even the documentation of Soarer's converter tells you to use 0x31 instead of 0x32... So does that mean that 0x32 is obsolete? How about 0x64?