I am following through the tutorial with the latest MPS & IDEA. I got
to the point where I am supposed to create a root node "HelloWorld" in
the model that I just created. I get a contextual menu: "Create Root
Node" with submenu: "TheSimplestLanguage" with a grayed out contextual
menu: "empty". I'm pretty sure I completed the previous steps
correctly. I can see the generated Java source within IDEA.
~ Dave Smiley