Conviction & Cold Mastery

[lisk]

When sorc hit monster(s) with Conviction on them, how Cold Resistance calculate? First, Cold Mastery lower it (to 0% max), when Conviction (maybe below 0%)? Or vice versa?
On the other hand, some Hell monster have 200+ CR, so maxed Conv & CM only lower their resistance to zero...
I thinking about small LAN party (maybe such thinkings not for Workshop <_<): pal - avenger with one-elemental sorc. Which elemental she may choose? Cold with moderate damage, chilling/freezing and some cold resistance monsters (in 1.09, how many in 1.10?) Or fire with high damage and frequently fire resistance monsters (again, in 1.09)?

[Pren]

Cold mastery was supposed to be changed to be a direct reduction, and pierce immunity. It reaches astronomical levels of reduction now at high levels, but according to people it doesn't work.