I paid out $60 for this mouse because the copperhead I bought was so uncomfortable to use, while gaming I got cramps in my hand. Button five does NOT work when it comes to mapping a KB key or using it as a macro. Yet any windows function (Dbl click, Paste) works just fine telling me the button does work. I play Battlefield series a lot, and I map Ctrl to thumb button #5 to kneel in game, but it doesn't work. What really ticks me off is...Razer has given me zero support via the phone, or the web. They just wanted to send me another mouse after I sent mine in...a three week turn-around. I don't think the problem likes with the mouse as the button seems to function find with Windows commands assigned to it, but wont simulate any key stroke. I believe the software or firmware has issues. I think a new mouse would so the same thing, and am quit pissed off. They said they would get right back to me and it’s been over a month. The only good thing I have to say is...Razer finaly designed a comfortable mouse, now I just need to sinsere support.