Line Conversions and Bsurfaces with Blender 2.69 My problem is converting a path into a bezier, and a bezier back to a 
Grease Pencil again (or path to Grease Pencil),
since I need the handle assistance in Edit mode for those to get my shapes just right, and free handing with Grease
Pencil isn't accurate enough for curves to start.
From there, my second problem is turning at least 2 Grease Pencil Lines
into the opposite edges of a corelative surface, using BSurfaces.
I can't get Bsurfaces to run.


What state do 2 opposite beziers need to be in?
Do you have to start from grease pencil only?

How do I get Bsurfaces to show me the Add Surface
button, to draw it's extrapolation for me? 

I've found
the buttons, keys and mouse click too confusing here.
I'm not sure about converting back and forth between a grease pencil stroke and a curve, but you can create a surface from grease pencil strokes like this:

Enable Bsurfaces in User preferences &gt; Addons

Create an empty mesh by adding a primitive and deleting all the geometry from edit mode &gt; Delete:


Add a new grease pencil layer in the 3D view &gt; Properties region (N) and select Surface:


Still in edit mode, (editing the empty object) draw grease pencil strokes on the target object with D+LMB:


In the Tool shelf (N in the 3D view), press Add surface in the Bsurfaces panel: