I did the first mission tuesday last week on my way to the mall. It didn't seem too bad, though my feet were rather sore and bordering on blistery by the end. However i was annoyed when i finished to find out that the app hadn't recorded my path or distance at all.
So i decided to give it a try again today, but this time i waited on the start screen until it said it had a GPS fix and gave me a green checkmark, even though i never had to worry about that with the regular Zombies Run! app. So i got to the end, and discovered that once again it had failed to record anything =P
I've tried to recreate both runs on Google Maps. If i did it right the first one was 2.5 miles/4.0 km in 37 minutes and 42 seconds, and the second one was 2.6 miles/4.18 km in 36 minutes and 30 seconds.
I'm going to have to experiment some more and see if i can figure out how to fix this problem somehow, because having to keep track of the distances myself is really going to suck, plus it means i don't get the advantage of the analytics that the app is presumably supposed to be doing.