I made marshmallow fondant for the first time yesterday and it seems to have turned out well however I have a couple of questions. Does it dry hard with out adding anything? Do I have have to use Gum-tex in it to make decorations and if so how much. Thanks.

MMF will not dry hard unless it's really thin and sits out for a few days, so if you do want your decorations to be hard quicker than a week yes add gumtex. I honeslty just sprinkle a good amount on top of a small batch and just knead it in so no idea what the exact amounts should be lol.

I never add gumtex to the decorations unless it should be hard like bows and figurines.