Its ALOT harder than kino which i've gotten to 45 in by myself.
What i do is get the usual perks (Revive,Juggernaut,Speed Reload) by round 10, and have BOTH blockades on level 2 opened up.
Snag a mp5 off the wall and run around the bottom area in a circle behind the stairs and in between all the computer terminals; unti a maximum amount of zombies are spawned then i'll pick them off once they are grouped up.
I try to get claymores early as possible and place as many as i can in the elevator by double tap for when the scientist comes,
If he runs into 6-8 claymores and then takes a clip from the mp5 he will drop, And you can use that to your benefit if you pull it off quick enough to get a cheap pack a punched weapon through the bonfire sale.
Work on avoiding the zombies when they start coming in the beginning of a round more than shooting them, once they are all behind you and you do a few laps to get used to the weird angles and areas they will come from you should start shooting.
Perfect your Juking Technique and be very aware of where you are running, its alot easier to get trapped in a corner here than it is in the other new map.
Eventually you will rack up tons of points and get the upgraded Frostgun and whatever gun you like as a backup, rounds 16-25 i'd rock an upgraded MG of any sort just to get a ton of points up and then you start to need something that deals out more damage...
As soon as you get the WinterzHowLololz you just stick to the usual strategy and run in circles until you can guide them down one of the walkways where they will all be lined up and fire enough shots to make them freeze,
Then whip out your backup to clean up ( At this point and all throughout the level you should keep an eye on the top floor for how many zombies are respawning so you can judge when you should take out the 'group' and so you don't turn around to fire and get smacked upside the back of your head!)
You really have to conserve your ammo as much as possible.
Rounds 30+ will really test your abilities to survive, good luck with the max ammos :)