Hi,
In the old PopcornFX v1, there is a tool to render a sequence of PNG images to disk, but not yet in PopcornFX v2 unfortunately.
However, we do have something in development that might interest you regarding the last part of your question :)
There's still a fair amount of work to be done, and we'll probably be sending out some previews to a couple users in ~2 months, if you're interested you can drop us an email about this on support@popcornfx.com and we'll keep in touch.