Don’t use this block. Ever. Well, except if you need to initialize a list or set the value of a list.
Your app variable Skin List is already a list. When you add that block, you create a List of Lists which you want to avoid.
Longer explanation: The blocks you used are going to get the value of the variable which is {“Skin1.png”, “Skin2.png”, “Skin3.png”} and then make a list from it so that would be {{“Skin1.png”, “Skin2.png”, “Skin3.png”}} and then get the app variable index item from that list. So if you get item #1, you’re getting {“Skin1.png”, “Skin2.png”, “Skin3.png”} but if you get item #2, you’re getting a null value since {{“Skin1.png”, “Skin2.png”, “Skin3.png”}} only has one item.
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