A chocolate warmer like a Mol d'Art is not a tempering machine. You really should know how to properly temper chocolate in order to use it. One way to use a melter is to melt the chocolate but never take it out of temper (not get it too warm). You can also use the sous vide method to create what's called cocoa butter silk to seed melted chocolate. A lot depends on how much chocolate you need. And - learning how to properly hand temper is not a skill that will ever go to waste.