The workflow should be very similar to werkkzeug, my tool is only a wz clone, with a different editor, render engine and render features.
For example, actually main procedural content (bitmaps and meshes only) is exactly similar to wz4 because I made a wz4 library that contains the procedural texture and mesh generation of wz4 and I can import it as a plugin inside my tool.
As all operators in my tools comes from modules that you plug in, I'm also working on alternatives modules to generate others procedural content, like textures from gpu, or meshes from revolutes and lofting techniques...
a little screenshot : what are you seeing ?
- 1 mesh generated from the wz4 library
- rendered with my 3D engine (OpenGL based for portability)
- and painted with built-in materials (actual shader is a single pass solid wireframe - like explained here here