I have both 209 and 109 model and I'm struggling with this.
On Linux or Windows, there are no difference with them about Left spacebar.
Both models outputs International6 keycode.
I checked it by capturing USB HID protocol packet.
In spite of these results, Mac OS X doesn't recognize International6 key.
I asked what happens to PCKeyboardHack Author, he said "if Mac OS X recognize key press, it is recognized as typing 'a' key if the key is not mapped correctly."
With 109 model and without PCKeyboardHack remapping, I checked typing left spacebar is recognized as "a".
With 209 model on same condition, nothing is typed.
Now I doubt HID Page number is correctly set.