Before I first launched Sculptor, I viewed the feature tours and getting started guide. I think got started, and decided to create a sample page one step at a time, to see how it progressed, I chose a simple layout and saved it.
The very next thing I did was to look for the wizard again to make some edits to my layout. After an hour of that, I finally came here and did further research and discovered what this thread is about. I was let down, because I was excited about this tool to start with.
Yes, I assumed this was possible - basically because every other extension in the world provides re-entry and editing. So, it's still useful but not to the extent I had thought at the time.