Alright, straight from the 'peg, winter in a nutshell.
Think Ice, even on streets, October-November and February-March are the absolute worst for cold here because it's half-way into the freeze/melt (the second half is the worst)
Why that is bad, primarily it is a hazardous situation when you have lots of half-frozen water around in the process of freezing and re-freezing, it creates an effect we call 'Black Ice' almost indistinguishable from normal pavement it is the slipperiest substance winter can throw at you.
If the ice is white, you're fine, but unless you're wearing cleats of some sort, you are likely to go head over heels on the black ice if you don't know how to walk on the stuff, double those chances if there's been a light dusting of snow over the black ice.
Now then food growing, you're probably looking at a mainly hydroponic / water body living society if there's going to be any perminant settlements.
However, getting through the ice is going to be very difficult if you don't have the right tools, you can't just smack a hammer on a section of frozen river and have it knock a hole right to the water, otherwise you couldn't even walk on it in the first place.
There are specialized tools such as ice drills to punch a hole through it manually, these ice drills are normally 4-8 feet long depending on how deep the freeze is (the local river is about 3-4 hereabouts.)
Another method of keeping the water from freezing is having an agitation machine in the water, if the water is turbulent it won't properly freeze over and will remain a slushy morass close to the thresher, allowing access to the water if need be.
As for heat, with icy weather such as this, most of your power is going to come from either existing power plants or solar panels, reason being is that most foliage is going to be dead or hibernating so there isn't going to be a lot of leaves in the way.
Another tactic for staying alive is using the snow itself to insulate your abodes, meaning half-buried houses are going to be the norm, in order to properly keep you warm WITHOUT having a lot of energy wasted on keeping the house heated through the means of energy above.
The only reason why we don't do it now is because winter does not last more than half a year, so the cost to move all that snow isn't worth it against the savings in heat we'd get, also many structures aren't designed with that idea in mind.
Another winter hazard you're going to have to watch out for is windchill, your thermometer says it's -25C (Celcius, approximately 30F) however the windspeed causes skin to freeze faster because it takes heat away from your body that much faster, making the effect on your body equate to it being outside in a far colder day than the thermometer says.
For example, it's been -20 to -25 here, however the windchill, based on wind speeds and direction, have made it go to being as cold as -50 on the worst days and -35 on the best days up until two weeks ago here, now thermometers can't read windchill, so they happily say -20, meanwhile with the wind you're chattering your teeth to a balmy -40.
Also snow storms, hail, white-outs. drifting snow are various visibility hampering conditions where the snow is in your face, hail is not common in the dead of winter, it usually happens during the beginning and end when there's lots of moisture in the air that can collect to the snow as it drifts, forming the hail.
A white-out is simply that, you can't see further than 10 feet because the snow, even on calm wind days, is falling so profusely that you are literally covered in white after the first 5 minutes you are out there.
Drifting snow only happens on high-wind days that are also very dry, quite common during the dead of winter, all it does is clog up the sidewalks mostly but if there's a good wind going it can obscure vision a bit.
Now then, effects of snow and your clothing, forget all that big bulky rubbish, layers is the key to surviving winter climates, the warmer it gets, the more layers you take off, the colder it is, the more layers you put on.
The key is your boots, and by proxy your lower legs, you see you're going to be truding in at least 2 feet of snow, most people forget that and wear running shoes, big mistake, you are gonna give your ankes a good case of frostbite if you pull that for too long.
You want a pair of boots that are ankle high at LEAST, also waterproof, you may ask why that is so, it's for the last two months before the thaw, because it's going warm and cold, warm and cold, warm and cold, and that creates slush.
Slush is a messy, dirty, and altogether annoying substance that occurs when it's not quite cold enough to freeze, but not quite warm enough to melt everything, you wind up with pockets of this slush in well travelled areas, now on it's own it's harmless, if it warms up enough you wind up with a locked puddle until the drifts on either side of it warm up enough to allow access to the ground and the ground is warm enough to be porous again.
However if you put your foot in it, it's what's known as a 'Booter' literally you get a bootful of the coldest water you can imagine, now if you're on your way to a nearby building it's only an annoyance, however if you are in mid-trek and you have a long way to go yet, it can be a serious problem, because anyone can tell you, wet is BAD in winter, because wet can freeze.
That means you don't want to sweat either, so if you put on too many layers you can freeze yourself just as well as not on exposed parts of the body that are sweating because the rest is overheating, you need to find the balance that's right for your body.
Another problem with winter is hypothermia, by itself it's harmless, effectively when you are too cold, your body's immune system suffers, hypothermia is effectively your body saying I'm too cold, however with your immune system weak like that, even a common cold can run havok on you. Normally hypothermia isn't what kills you, but the flu that makes your hypothermia noticeable.
I believe yellow snow has been joked about but it is a big problem in settlements without water treatment plants, you can't just take a fistful of the nearest snowbank, there's all sorts of crap in that you can't even see, your best bet is to have a collector nearby that collects snow as it drifts down OR purify snow by boiling it, although creating heat with electricity is extremely inefficient it is the only way to kill all the germs that could be in ground snow.
I think I covered the basics, there's little tricks like snowshoes that allow you to walk on top of powder snow without going waist deep into it, effectively it's a tennis racket but bigger and it distributes your weight across a larger space, allowing the snow to be able to support your weight.
Anyways, hope this is handy...
Concerning your engine question Ausdoerrt: FIFE doesn't feature support for 3d models and the decision to use a 2d engine was an intential one.
