This isn't going to help very much but the standard operating temp of an engine is whatever it gets to if it's tuned correctly (somewhat rich from full peak) and there's sufficient oil in the fuel. Other than that, there's nothing you can do about the temperature. As a guide though, one of my engines runs at about 300F when fully peaked, around 295F when richened a little and I've had it down to 145F when run slobbering rich almost to the point of cutting out.

As for running in an engine when it's very cold, cold for me is when it gets below maybe 50F so I've got no experience with what some of you guys call cold . But seeing I like to experiment, I picked out one of my engines that has a very nice pinch at 65F without the plug fitted and put it in my freezer for some time. I got it's temp down to 23F and rechecked the pinch. Surprisingly it had lost all its pinch! This is the opposite of what I expected but I've found some strange things with ABC engines . Letting it warm up again to room temp restored the pinch.

This is the same engine I experimented with when it was new by running it extremely rich to see what sort of damage would be caused by not letting it heat up to normal temps. I ran it for 45 minutes slobbering rich (that 145F temp) then stripped it. There was no damage whatsoever and the piston looked brand new. I had to lean it out into a 2 stroke to get it to run in. The write up I did here in RCU about this experiment caused huge controversy . Personally I wouldn't hesitate about running in an engine with very cold air temps.

As for airflow, this of course has an affect but after another experiment (also detailed in RCU) it seems that with the pitches and revs we use then we don't get anywhere close to having too little airflow. I compared the temps on an engine using both an 8" pitch and a 3.75" pitch props and the temps were identical. And at one stage I put the fine pitch prop on backwards. That's an old trick used by CL fliers sometimes to slow a plane down if there's no suitable prop handy.