The Large Wall segment has always been bugged or problematical since EA.
I guess the Large wall segment is not designed to accept doors as its ideally suited to using as a perimiter wall or boundary wall.
I am not at all sure what the scripts for it contain as Ive not looked - perhaps one could make a copy of all of its media and set it up as a single segment wall but specifying in its script the parameters contained with reference to standard room segment script parameters.
I have not checked to see if the specs are different.
I have done this kind of thing by using a single plain default room segment wall entity .x file and a rooms segment script file and editing the script so that only one (the entity mentioned) wall is referenced and contained in the script. I use this as an invisible wall segment to place around boundaries of outside levels. It works fine placing single walls - you just have to rotate the arrow indiactor at corners to paint the walls as you go.
Needless to say when I made it I avoided using the Large Wall segment as as basis I knew there were issues with it.
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