Currently commandline support is broken in the Technology Preview. This will be addressed in an upcoming patch.
I would think a frame manager ought to have the capability to call a commandline app and specify a new frame number each time. The way TG 0.9 worked with commandline rendering was you would call it, specifying a world file, terrain and script file, and then specify a frame number. The "exit" switch would be on so it would exit the app after rendering the single frame. I do believe you could also do frame ranges actually, but still I would think a decent frame manager ought to be able to handle this just by iterating its own commandline string, rather than depending on the app for frame range handling. This makes it far more flexible since it can even animate with apps that don't explicitly allow it.
- Oshyan