Fast travel to Dragonreach's ends up in void?

[jwbatey]

In my mod I've added an underground city and allow fast-travel from it.

Normally fast-travel works fine, but if I try to go to a certain zones (Dragon Reach, Blue Palace) from my new city, the character ends up in the grey void. Doing anything (except hitting escape) will then freeze the game.

If I try to go to any lo0cations in the Wilderness, it works fine.

Any ideas?

 

Link to mod is: http://skyrim.nexusmods.com/downloads/file.php?id=9275

(The zone causing the issue is reachable via 'coc jdwem' - fast travel from hear to DragonReach gives a grey screen - Esc key still works)