@leceta
I´m grateful for your help, and for sure I will check that link.
Look, my line of thought is quiet simple, just follow my line of thinking ....
You have a GH component capable of opening your loaded ArchiCAD Library, can see each object, and if permitted it can manipulate the object's custom GDL Parameters, and implement the desired change per object & instance.
So if you're able to that from Grasshopper, why can I export those values to a panel in Grasshopper ???
Cause if you were able to do all the above, and the object GUI is able to read the the object's parameters and values, that means their is a connection that already have been done, but it doesn't include this aspect.
Sorry for the long reply, and thank you again
A good friend of mine have once told me that I´m so brute that I´m capable of creating a GDL script capable of creating GDLs.