I've noticed that assigning a keyboard shortcut to a button on my Signature M650 (such as cmd-M to the scroll button) doesn't work in all applications. Nothing happens with the button press. But if I assign the same keyboard shortcut using the global settings, it does work properly. I've observed this behavior in the Chromium browser and Reaktor 6 Player by Native Instruments, as well as applications I've written for the Mac. Any ideas?