Nah, I just hang around the lander pad, the one next to the HD Flopper... or whatever it's called. It's not that hard once you get going, sure by the time the round is almost over all your ammo is gone, but the points you get out of that round you have enough to go to the box as many times as you want and then upgrade the weapon.
And yea I've played Shangri-La (well I've played all the zombie maps), in fact I was playing it today trying to get some Achievements for it. Not really fond of that map...