I can't remember who told me but that model was done in an earlier version of ArchiCAD ie pre Curtain Walling tool. It was in fact done with GDL objects custom made to do the job.
So it's all smoke and mirrors, they never said it was modelled with ArchiCAD 12
AC versions 3.41 to 25 (UKI Full 5005).
Using AC25 5005 UKI FULL
Mac OSX 10.15.7 (19G2021) Mac Pro-2013 32gbRam AMD FirePro D500 3072 MB graphics