There isn't a user manual or parts diagram for these old lathes like the ones for the modern far eastern machines. On the Drummond site you will find a sort of brochure with a few pictures of the lathe in use to show possible set-ups. There is also a copy of the 'Know your lathe' book which will give you an idea of how to use one.
Can you find it on the lathes site? Never heard of a 'knee planer' in relation to a lathe.
Have you moved on from the round bed? Try and work out how to post a picture on this or the yahoo site as it will help us to help you. If you can undo a few of the nuts around the change wheels, pretty much any of them, you will release the leadscrew from the main spindle and can see which / what does move.