Keith Kolbo's FrameForge 3D review suggests a different way to use this tool.
Instead of just emulating the use of pencil on paper, you build a simple 3D set from libraries and scoot around it and take snapshots for each storyboard frame. This is far easier than in a general purpose 3D app.
When set up correctly, the end result also contains a lot of shooting information: focal lengths, camera height and position, actor positions, etc.
Maybe I could get used to this... (I am used to stick figures, which are often OK but have limitations when talking to other people).