clickbar with middle mouse button or any key

I'm trying to make click bars that take a bit more input than LeftClick, RightClick, and mods of these.

For instance I'd like to be able to click mousewheel or button4, 5 on my mouse, or even a numpad key while mousing over a click bar.

Is there a way to achieve this? If not, are there any alternatives to get this to happen?

To get it to happen, you can use a mapped key on the mouseover of a click bar. That mapped key loads a key map, which has a bunch of other mapped keys which have the hotkeys you want, like mouse middle button, mouse wheel scroll etc.

This kind of thing is covered https://www.youtube.com/watch?v=Mizu6e6BEno and http://isboxer.com/forum/viewtopic.php?f=27&t=6593