FM 2017 missing menu bar

I have been using FM 2105 on a virtual windows machine through my mac, but have just bought a laptop to be a dedicated FM machine and have FM2017 downloaded. All linked to the dropbox files, all looks good.

When I open a book, it shows all the files in the book on the left. Then when I open one of the files, the top menu bar with File/edit/view/xlst/window/help disappears. Nothing I can find an get it back.

Then when I shut the file, they remain invisible until I click on the </> button whereby they all come back.

I can't edit any documents as I need that menu!

What's going on (or what have I missed!).