OpenMW-CS: Converting an esp to omwaddon has some quirks.
There are some issues with cell references at the moment when converting an esp file to an omwaddon file. For example, editing an instance's position causes it to disappear from the Instance table. I suspect the Dark Brotherhood.
#5 Updated by Kyle Cooley about 1 year ago
That's the problem with unstated rules. Anyway, it looks like the wiki entry for reporting bugs regarding this matter was modified in Dec 2016. It currently says to insert OpenMW-CS before the beginning of the entry.