Well, this has to be (hopefully) the simplest request ever, but I couldn't find any solution through either google and forum searches.
I plan for my game to check when the player opens the inventory for the first time. In the grand scheme of things, it's just a small way to double-check if they have opened the inventory prior to a specific point, to which if they have not they are informed through dialogue what the key to press is.
Right now, I've got a parallel event that checks for the player to press "Cancel", and if they do a switch turns on.
Unfortunately, it's not quite enough, as players are free to press cancel during cutscenes or dialogues and the game will then believe they have opened the menu.
I'm assuming this is a fairly simple affair of checking the first time time the inventory screen has been opened (instead of checking for the button prompt itself) and turning a switch on - but as I'm totally ignorant when it comes to javascript, I hope someone can answer me back on this.
Thanks for the time!