I use an earlier version of the dehydrator you just ordered to dry them and an old coffee grinder dedicated to that purpose to grind. I don't move huge volumes though and I'm fine with a quick and easy powder grind. If the pods aren't thoroughly dry though it's a pita - and definitely don't let them sit around after turning off the dehydrator or they'll quickly pull ambient humidity and hello pita.
I think SMDS's method and saiias' method can be really effective for a quality work, such as flaking peppers like aleppo or urfa biber.