I'll be honest, these are incrediby hard complex to program in, so don't expect them anytime soon. There are lots of other features that will give a better payback for investment. One huge thing we need right now is help texts on how to write good stories and use the editors.
Your first question you can workaround by this. Let's say you have an item called HEALTH POTION and you want it to give the user 25 HITPOINTS when they USE it. Make a page called Drink Health Potion. On the page say, "you drank the health potion" and add a single link called "Continue ..." that takes you to the previous page. On the link, add a variable change to increase score by 25.
For the second question, maybe. A feature to be implemented soon is the ability to have a link automatically drop an item. Once this feature is in, you could have the EQUIP CHAIN MAIL link drop all armour items except Chain Mail.
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