What type of chocolate is used for molding?
The dough-like texture you mention makes it sound like you burned your chocolate. Remember, a bar of chocolate will melt in your pocket so it really doesn't require much heat to melt.

To use a microwave, break the chocolate into small pieces and stir every 30 seconds even if the chocolate is still solid since the microwave will heat the pieces unevenly; it shouldn't take more than about 90 seconds in total.

Using a water bath, make sure that the bowl is not in contact with the boiling water (to be honest once the water has boiled you should be fine leaving the bowl in place and taking it off the heat, letting the residual heat warm the chocolate).



Additionally, I would recommend 'How to Cook That' and its YouTube channel for good clear videos about how to melt and then use chocolate. In particular if you want to mould your chocolate you will need to learn about tempering it, and the guide on that YouTube channel is comprehensive and reliable.