I assume 'multi sash window' is an object.
Do you have that object library loaded?
Or maybe it is controlled by an add-on?
If so you will need that add-on loaded.
Your old files should work just as they did before (assuming you have the same add-ons loaded for 18 that you had in 17) with the exception that a whole bunch of new Building Material attributes that get automatically created (which comprise of the fill, pen colours, priority strength and surface (old material in 17)).
Barry.
One of the forum moderators.
Versions 6.5 to 27
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