That message in your image, is just telling you that when the file was created (on a different machine probably) that there was an add-on used called AUS door/window builder.
You don' t have that add-on installed so it can't be used on your machine, but it will retain the data in the files so it can be used again when the add-on is installed or is opened on the original machine with the add-on present.
As for the report saying 'threat detected', that sounds like your anti-virus software.
You may have to set it so it ignores all Graphisoft programs and files.
One of the forum moderators.
Versions 6.5 to 25
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
Dell Precision 3510 - i7 6820HQ @ 2.70GHz, 16GB RAM, AMD FirePro W5130M, Windows 10