I'm not much of a c++ person. But i think you would have to edit it in c++ and change the hotkey. There's probably a command that binds the key to open the menu, you would have to change that and you should be done. But don't listen to me, I'm c++ uneducated, but i think that's how it goes, i used to know Java.
Then of course you would have to build it to check if anything is wrong, probably shouldn't have anything wrong if it was a working hack. Only thing that could come up with an error is if you input the command line right or not.
If you don't know what your doing then i don't think you should attempt it.