Possibly a reference here to the people the cipher is intended for. Someone in the know. Finally you will notice that beneath the N is a small dot. The size of the dot would seem to indicate that it was placed here deliberately. I single dot means Archetypes or Unity.
Archetypes are graphic shapes which combine in various ways to express occult or hermetic ideas.
It may seem a little far fetched to consider such symbolism as relevant in the decoding of this pictogram but it is worth bearing in mind certain points. The church and the various groups such as the Albigensians whose history permeates every pore of this region have used symbolism throughout the ages. B renger Sauni re was well aware of it to a very high degree as can be seen from the mass of detail in the church which he rebuilt from the ground up. Every single object is absolutely bursting with symbolism. Symbolism incidentally, which he gave considerable thought to before instructing the craftsmen to begin their work.