Strange keyboard layout for Japanese 106 key keyboard

[Rahlubenru]

It doesn't seem to work as either a standard US/Uk keyboard or as the actual layout for the Japanese keyboard which means that I am unable to complete the "A New Home" mission as I don't have an underscore.

How does the game decide what keyboard layout to use as changing the keyboard layout in windows to english uk results in exactly the same behaviour.

I had to change my keyboard driver to work around the issue, I understand it's a bit too obscure of an issue to do anything about really however so I'm not expecting anything to come of this. Not sure where some of the key mappings came from still though.