Dormer windows keep automatically re-sizing

[Otto]

I have created 2 auto dormers, using HD Pro 8.
For some reason (user error?), every time when I close and re-open the file, the following two errors occur :
1) The width of the windows changes (both windows, same dimensions!)
2) The windows are not centered anymore (both windows move in the same direction off center).

The result is that, every time I close and open the file, I have to manually center the dormer windows and re-size them.

I have deleted and re-created new windows in the dormers but that did not make any difference. I am unable to use the "Center Object Edit Button" on the dormer windows (error message: "Ambiguous location for centering along a room edge, centering will not be done. Please click near the wall that defines the edge of the room you wish to center along").

Any suggestions.............please?