It's done! This is a helper plugin for Box2D+ that gives you full control over a Box2D+ physics object so it behaves like a player with the platform behavior. This mod comprises 2 plugins:
Box2D+ Platform
Behaves like a top-notch platform behavior.
Box2D+ Flow
Controls doors and floors for one-way collision filtering.
This works with minify and gives good performance on mobile phones - no stuttering/jank on my testing. Check out the demo and instructions, links below:
Demo. If you're on mobile then you can use screen controls.
Instructions. Please read them so you know what's involved.
To obtain a free copy, please visit the link below to download the latest version. NB that this requires Box2D+ and will not work without it.
Download.