I got a reference to the button and inspected it in the console and it is indeed instantiated.   So it looks like I just need to dive into the style and theme settings as it is not applying any style whatsoever.   I expected the default look to match what is in the docs, but I guess not?  Anyway, if you see anything I am missing please let me know.
We are very much looking to buy because we want the tree,  but I need to confirm the basic usage first.