Here is a recipe for a MMF that is easy to make, rolls out nicely without tearing, and tastes great. I don’t live in a humid climate, so not sure how it works in humidity. This fondant is all I ever use.
http://artisancakecompany.com/2012/11/the-best-marshmallow-fondant-recipe-ever/
Toni, Pennsylvania, https://www.facebook.com/WhiteCraftyCakes