I've seen two buttons in scrolls: one for "Write Magic," which must be spell ability 1. And this one is actually pretty interesting: multiple spells can be learned at once, if there is more than one Learn Spell effect in the stack and the item is set to "Item recharges" or "Item remains." The scroll is still consumed, but the engine rolls separately for every spell, and some may be learned but not others. If the caster knows some of the spells, only the unknown ones will be attempted. The failure-to-learn screen is shown if any spells go past, but the rest still makes it. If all get learned, the success screen appears. If the caster misses out on one of the spells this time, the scroll is still green to him and he can try again with the same type of scroll in the future and pick up up rest.
In principle, now that I think of it, at the end of the Learn effects it may be possible to attach a Create item for this scroll again so that it's really multiple-use. AD&D scrolls don't contain one spell, they contain several.
The other button is the usual button for conversable items. If I wanted a talking scroll... Is it possible to place another button there? What are the limitations on code? I've asked kjeron about an option for xeroxing once, but I was still thinking in terms of dialogues then.
