Thanks for attaching the image. I understand now! We are talking about using 'Lists' rather than 'Schedules' to create a window schedule. This is what confused me!
Unfortunately I don't know much about lists, but I presume duplicating an existing one, seeing how it is put together, and then modifying it would be a good method to learn.
I'm not sure of your experience level with ArchiCAD and its features, but I'd say Listing is certainly in the 'advanced' section of things to learn, and can require a fair amount of setup before it is useful. I don't know if this is the case for a window schedule.
Perhaps someone else who uses Lists could comment and give some advice about setting it up, and advise about any complex parts you should be aware of?
Sorry I can't help much further. Good luck anyway!