Ok, this is going to make me sound really novice, but I have never really used the Block Editor.
EDIT: I figured it out... BSAVEAS, then Check the 'Save block definition to drawing file' box. (Uploaded file updated)
Here's the newbie question: (For what I anticipate is going to be a very simple answer, the problem is hard to explain, but I'll try)
How do I get the block I created in the block editor ... to ... work right?
I'm in a dwg file, which I THOUGHT was going to be the block. Well, it IS, but when I go to insert it into another drawing, the DYNAMIC block is nested inside the dwg file I've saved.
In my whole CAD career, I've only ever used WBLOCK to create my blocks... or create them from scratch in a new dwg.
Here... have a look. Then, we'll talk about why I can't get the attribute to stretch with the line work.