Unitron keeps freezing

Hello,
I’m very new to Unity. I’ve been following the book Unity iOS chapter 3. It says to create a javascript. I do and double click it in Project. Unitron loads up and I start typing the function and at a random point it freezes. The text editor freezes. I can’t close the typing window.I can’t undo. I can quit Unitron from its menu. I can look at all the menus on the menu bar. It’s all so very weird and annoying.

I’ve tried changing the text encoding to UTF-8 but it makes no difference.

Anyone have any ideas ?

I quit Unitron, deleted the object, generated a new one and it seems ok now.
And for some reason its turned into Smultron.