"Current Item" object in the subscreen uses the Item Class: "Letter or Potion"
When obtaining a letter, nothing goes in that object. When selected, you actually see the letter in the "button item" object. [SIZE="1"](same goes if the letter changes to letter (used) after presenting to a guy in potion shop room)[/SIZE]
When obtaining a blue/red potion, it does appear in the "Current Item" object. Ignore that.
In short, please fix the problem for the letter. It won't show in the "Current Item" object with item class "Letter or Potion" in the subscreen.