Right now Import Physics hasn’t been implemented in Blender yet, so does Export Physics has any use?
Another question. If I have a Blend file with a character in it, and I have already set up a ragdoll for it, can I append or link the ragdoll with the character to use it in another Blend file?
At the moment, Export Physics isn’t working, it throws an error when you try. Patching this up next.
Once it works, aside from importing it, you can also load it. Which is the same mechanism that the default assets use. They are all .rag files too, exported from Maya. Which is the second thing you can do, export from Blender and import in Maya. And soon Standalone and Web versions of Ragdoll.
You will soon be able to import physics too, which is useful in its own right similar to the Maya workflow. Especially for teams and working across multiple shots with the same character(s).
Yes, definitely. Anything else is a bug, let us know! You can link multiple characters too, except the will not interact with each other yet, since they would all have their own solver. This is where the “Merge Solvers” button in the menu comes in, but it has not yet been plugged in.
Sorry, just to confirm again. Currently, is it possible to set up a character with ragdoll in one Blend file, and then use the same character with the ragdoll in another Blend file? I have been messing around with Append/Link, but I couldn’t get it to work.
Yes, actually we made a tutorial on it earlier this week and I just now realised I only posted it on the Blender forums! 
I have a completely unrelated question. Right now, every hotkey in the Ragdoll button dropdown is shown as “Ctrl” to me for some reason. May I ask what the hotkey for Assigning markers is?
Ctrl is the key you can hold when pressing any of the menu items to get extra options for it. It pops up a little window with options you can tune for any given menu item.
There aren’t any hotkeys added automatically, but they can all be bound to hotkeys. Personally, I hit Tab and type “assig” followed by enter. Most of the Ragdoll menu items are rather unique, e.g. "repla" for Replace Mesh and "assig" for Assign and Connect.