This is not a direct answer to your very good question but perhaps there is another way to get what your are after. Why not do it the otherway arround? Publish your ArchiCAD files as a .pdf, then hyperlink the .pdf with any sort of content you want.
https://www.screencast.com/t/8d9aNrse You might also want to Append the link to the .pdf. What that does is retreive the .pdf and add it to the .pdf document. I don't know what the end result you need is. But quite often the deliverable/product is a .pdf anyway and might be a more useful file format to the end users ? The .pdf is as close to a universal file format as anything else.
Clasificatoins is probably the best place to add a link to an object that will open a .pdf
Several ways to do it depending on how you want that content to be viewed.
In an interactive schedule that contains the link to your .pdf for other content can be opened in your browser. You just move your mouse cursor over the link in the Schedule and a pop-up will say "Open link in browser"
When/if you do something like this you will want to save the .pdf you want to link to the object in something like Dropbox, OneDrive.... for the sake of generating a link address. I was not able to use the Windows "Copy Path" and and get that sort of link path to work in the Interactive Schedules. Still working on that.
UPDATE: Got the link to work by adding // to the address generated with the windows tool.
This is just one way to add .pdf links to an object, other ways too, but you get the idea I hope.
ArchiCAD 25 7000 USA - Windows 10 Pro 64x - Dell 7720 64 GB 2400MHz ECC - Xeon E3 1535M v6 4.20GHz - (2) 1TB M.2 PCIe Class 50 SSD's - 17.3" UHD IPS (3840x2160) - Nvidia Quadro P5000 16GB GDDR5 - Maxwell Studio/Render 5.2.1.49- Multilight 2 - Adobe Acrobat Pro - ArchiCAD 6 -25
