Can I comepletely replace MMB with a key

Having only two buttons on my tablet pen, being able to somehow replace the Middle Mouse with key would really rule…

OR

At least replace the function [which I do not know how to search for] when you click MMB while Scale/Grab/Rotate, which allows you to lock onto an axis…

Thank you so much for assistance!

Cheers

User Preferences / Input / enable ‘Emulate 3 Button Mouse’
MMB = Alt+LMB

Ah shucks, I already have ALT for rotating/panning/zooming :frowning: