My salesman came running in, what have you done it's all gone...

First lesson when a salesman says he hasn;t doen anything, add a pinch of something smelly and ask again.

Seems he had just reordered the main contents. This has the effect of changing the Home page.

The top non sub room link in the main contents becomes the home page.

To fix this, go into Customise this place, and reorder the Home page to the top of the list.