How to get the 2 ovens on my Carron Cordon Bleu 4 to work?

The above cooker was left in the house we bought. The top four rings, griddle and grill all spring to life at the touch of the ignition button. Neither of the two ovens even appear to have any gas coming through. There is also a strange lever protruding from the very bottom of the stove that appears to do nothing at all. I would be grateful for any advice, also the whole thing could do with a full on clean as it appears it was owned by a bachelor !!!!