npc followers fall thorugh floor when entering a door

[dustierapple]

its me again just wondering why are my  followers are falling through the floor when walking through a loading door to the back door outside of my house mod whilst i have got the navmesh finalized and corrected and i have tried replacing the door markers that did not work, and i need to know what i need to do to stop this im a few minutes from finishing the mod completely any help would be most appreciated 

[Tamira]

Could you upload your file so that someone can have a look at it?

[WillieSea]

Do you have 'door markers' turned on and visible in the construction set?

 

And are you sure there is not a 'nav-mesh' below the ground that the NPC's are gravitating to?

 

They should go to the 'green' triangle on a properly finalized navmesh that is nearest to the door marker.

[Hanaisse]

One thread is enough. Use your existing thread please.