Hi Owen,
I have found published SDK for GstarCAD 2022. I hope it allow a support for GstarCAD 2022.
https://ovsdownload.gstarcad.net/software/GstarCAD/2022/EN/grxsdk_GstarCAD2022.zip
https://www.gstarcad.net/developer/
Reagards
Mateusz
I have added a GRX2022 module (untested) in OpenDCL 9.1.5.1.