X1 Double Wall Looks Weird?

[Zowie]

Hi,
I'm making condos that have a double wall between units. I created a wall definition with the correct spacing, then butted 2 walls and labeled both "double wall" "frame through".

However when I draw a perpendicular wall to meet my double wall it wants to merge deep into the double wall instead of meeting it like normal. This looks really weird. (I think I attached a photo, but not sure if it's going to work?)

Do I have a double wall setting setting wrong?

Thanks very much,
Zowie