From the API 26 Development Kit example add-ons, the Automate_Functions project fails when performing "Do_Save_PdfFile". To be more specific, this method returns APIERR_REFUSEDCMD:
ACAPI_Automate (APIDo_SaveID, &fsp, &pdfPars);
Are you running Archicad in Demo version? According to the documentation (https://archicadapi.Graphisoft.com/documentation/apido_saveid) you'll need to run Archicad with a license to execute this function.
I think you are right. My bad. My license isn't upgraded to Archicad 26.