I have attended the Wilton's Class but my instructor suggested I not work with MMF. I have experemented with it some. In my class we used a mixture of gumpaste and water. What do you use with MMF?
to attach any fondant or gumpaste pieces you can use water, gum glue or royal icing depending on how heavy the piece that you're attaching is. Royal icing is the strongest, then gum glue and then water.
Gum glue is just bits of gumpaste broken up and melted in a bit of boiled water to make a paste. Keep it covered and in the fridge when youre' not using it. It'll keep for a few days but will eventually get moldy so be careful
You can also use egg whites. They work very well as glue.