There are two types of NPC's, leveledActors and just normal Actors (I dont have CK in front of me for the correct terms). Leveled Actors will set their level relative to the player when they first enter that zone (side note, if you're using or copying an existing zone, they are linked). Normal actors have their levels set to an absolute value.
You may be adding a normal low level actor.
In the CK render window, and leveledActor looks like a color "M" with an arrow sticking out from it (to show direction it's facing). A normal actor will render what the npc looks like. leveledActors dont render in CK cause their style, armor, etc changes depending on their level (a lvl 50 falmer looks more fierce than a lvl 6 falmer, the names are also different)