Easiest way to add 1 button

[simplygriff]

Hi,
I'm using MAS playstation to USB joysticks for my control panels and am planning on getting a Happ USB-PS/2 Trackball with 3 buttons and building an enclosure for it.  My problem is I don't have a dedicated exit button and want to add one.  What is the best & easiest (I'm no electrician:) ) way to add one button to what I have.  I can add it to the trackball enclosure I'm going to build but I don't know what to hook it up to to make it work.  Does the Happ interface allow for more than 3 buttons?  or can one of the connections be split or something?  Hack a keyboard (I'd hate to do this for 1 button)? or mouse?Thanks in advance for any advice.
-G

[SirPeale]

You might be able to map a combination of buttons for an exit.

[simplygriff]

I kinda thought about that.  I'd be using joytokey with Mamewah.  Anybody know if I mapped like a button to right shift button, hold it and press start or 1 would I be able to exit? So basically use two buttons to exit.  I haven't experimented with joytokey enough to find out everything about how it works.

-G