95 altima 2.4,machining head question

so I just got my head back from the machine shop.put the car back together, now when its warmed up(thermostat opens) it blows white smoke out back and has misfire.in the manual you have to torque the head down after you install timing cover...so my question is should I have had the cover machined off as well to compensate for the machining on head? if so I will be pissed....!but I really want to know whats wrong...I kinda think the timing cover didnt allow the head to seat properly on one side.please help before I lose my mind !!!thank you.

little update..now Im really confused..Dont think it's the timing cover anymore because I did a compression test and #1 165,#2 90,#3 70,#4 had 170 psi...wtf!its a new head gasket and everything was straight when I installed it....doesnt make sense but everything is pointing to bad head gasket....what ya gonna do..:confused: help