Ive used a number of methods to create clouds recently and this one i actually didn't end up using for the personal project i created it for due to aesthetic reasons.
I did develop it quite far however and have decided to release it via my studio ANALOG.Its basically a script/scene-kit that controls pre-made cloud objects, using FumeFX to emit volumes quickly and easily at a workable/manageable scene scale. Scene scale can be increased of course - but things will slow down. Ive tried to build things to be at a decent level of realism.
I hope to release this early in the new year once i have smoothed the maxscript interface out a little more and automated a few more steps in the process such as cloud mesh shape creation, being able to set and lock certain simulated frame/s for the clouds and adding an option to shape via temperature.
It will probably be free too :)
Cloud Creation Kit from Matt Chandler on Vimeo.