I just tried removing the stem on my NWT. Getting it started is the toughest, but I don't find it super hard....I need to get a good grip on the bars and hold the rest of the bike down with a foot or use a hand on the stem and a hand on the front rack...
It seems that your bike has the same problem as mine (as well as other people that replied to this thread).
Pulling the stem out with two hands while holding the front wheel between my legs does the tricks. Only problem is that by the folding sequence of the NWT, by the time I need to remove the stem, one hand already holds the bike so they don't fall and one feet is under the rear fork so it does not get into the dirt.
I will call them and see what they say.
Kam