Just did the mod. Actually made both buttons work. I used electrical connectors, one facing down and the other one diagionally. It took a while to trim everything to the correct length. It was worth it, it has the press and feel of the factory buttons.
FYI, enabling the front fog light switch on the E90/E92 m3 doesn't do anything. I guess its because we don't have fogs. I thought it might turn the indicator on though.
Thanks for posting this DIY!!