I would guess that your disk/registry/etc got corrupted when you had the power failure.
Run a full chkdisk (reboot required), run any maintenance software you have (e.g., to clean up temp files, etc) and reinstall ArchiCAD.
One of the forum moderators
AC 27 USA and earlier • macOS Ventura 13.6.2, MacBook Pro M2 Max 12CPU/30GPU cores, 32GB