Another helpful Quick Tips Video from Sephra - the chocolate fountain people.  

How to melt Sephra chocolate in the microwave to add to your chocolate fountain.

Simply place the 2 lb microwave safe, BPA free bag in your microwave; set the time for 2 minutes on half power; press start. Don't poke holes or open the bag in any way. Remove the bag from the microwave and knead with your hands. The chocolate will feel squishy, but not entirely melted. Place the bag into the microwave again for two more minutes at half power. Remove from microwave and cut off the corner of the bag. Pour the melted chocolate into the basin of your fountain.

Make sure the bottom piece of the cylinder is already set into the fountain before adding the chocolate, as it is much harder to set the cylinder on the pegs once the chocolate is in the fountain. If you continue to melt your chocolate fondue beyond the 4 minute mark, you run the risk of scorching the chocolate. This will cause the chocolate consistency to be somewhat like toothpaste and it will only worsen with more heat. Be especially careful with white chocolate as it is most easily scorched. I prefer to melt my white chocolate one minute at a time, always at half power, just to keep a closer eye on it. For more of Sephra's Quick Tips, check this:  The Secret to Burping Your Chocolate Fountain  - a must see!