I have a great holiday cookie recipe that I'm thinking of trying to "veganify." The original ingredients are:
butter, powdered sugar, vanilla, flour, dried cranberries, lemon peel, decorating sugars

Two questions:
-Would subbing shortening for the butter (a 1:1 ratio) work? Do I need to change the ratio or add something to do the sub?
-Should I worry about any of the other ingredients being not vegan-safe?

Note- I'm not vegan- hence all the questions.