Re: How to address Hz. Ali (RA)
I fully agree with Kaleem that Allah is the Qadir-e-Mutlaq and there is no one but HIM.
Allah has all the powers and He chooses to grant His subjects with power even the utlimate power to raise the dead.
I see no big deal in calling Ali as Mushkil Kusha as he was Allah's chosen helper to his greatest creation and our beloved Prophet (SAW).