If you're trying to set up a global hotkey in Windows, you can use the win32con.VK_* codes to set a hotkey that uses a regular character (e.g. Control-Alt-B), but on OSX it's not as clear. However, a quick look at the patch reveals that all you need to do is pass the ASCII character code for the character you want by using
ord() like so:
result = self.RegisterHotKey(hkid, wx.MOD_CONTROL|wx.MOD_SHIFT, ord('r'))
And now, when you hit Control-Shift-R, the event will fire.
For what it's worth, you can also use
wx.GetKeyState() to detect if a character has been pressed on the keyboard. Not sure how this works for international apps, but it works great for my purposes:
print wx.GetKeyState(ord('h')) # Prints true if the 'h' key is currently pressed