Not sure, with Keyclone.

Maybe, the IS Boxer solution might give you an insight for something to with within KC?



With IS Boxer, you would make a mapped key that uses the mouse as the hotkey.
And then have the mapped key output a key combination to the game.
With an ability on the key combination.

Abilities fire off of key combinations much more reliably, then setting them in Warcraft to fire off of a mouse button.