First a general note: Because of potential library bugs in a variety of parts, "always" look at the plan and axo views of a library part
inside
the settings dialog
before
placing the object. Any bugs will show up there, before placement, and avoid headaches down the road.
A quick test verifies the bug you see at the default size. If I make the window 5' wide, then there is no error. Alternatively, at small sizes, if I change the wall type to 'solid wall', the error message goes away. (I'm trying these things directly in the window settings dialog with the axo preview selected.) One of these will probably resolve your problem, but perhaps not with the final appearance that you want...
Being that this is in ac 10, no point in filing a bug report with GS. If it happens in the equivalent 11 lib part, then file a report.
😉
Hope that helps,
Karl
One of the forum moderators
AC 27 USA and earlier • macOS Ventura 13.6.9, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB