Have you tried 'MyArchicad'.
The link is at the very top of this forum.
Barry.
One of the forum moderators. Versions 6.5 to 27 i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10 Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11
As far as I can tell, MyArchiCAD only has current and one version back. All the goodies and hot fixes and add-ons are available. But not the installer.
Think Like a Spec Writer AC4.55 through 27 / USA AC27-6000 USA Rhino 8 Mac MacOS 14.6.1