The best way to move the cave is with the mouse. If you hold down the right button then the cave is dragged when you move the mouse. If you hold down the left button, then the cave is rotated if you move left or right, and zoomed if you move up and down. If your mouse has a middle button then you can use it to tilt the cave.

By default the mouse moves the cave, but if you press <Ctrl-R>, then the mouse will move the viewpoint instead (i.e. everything will go in the opposite direction. This seems more natural to some people.

<P> and <L> select Plan and eLevation respectively. Changing between plan to elevation is animated to help you see where you are and how things relate. This animation is automatically disabled on slow machines to avoid user frustration.

Comma <'>, and Slash </> tilt up and down respectively. Tilt goes 180 degrees from plan view to a view from directly below (upside down plan).

Enter starts the cave spinning, and <Space> stops it. The speed of rotation for this, and tilt, is controlled by <Z> and <X>.

Crosses and/or labels can be displayed at survey stations. <Ctrl-X> toggles crosses and <Ctrl-N> station names. <Ctrl-L> toggles the display of survey legs.

<Delete> is useful if you get lost - it resets the scale, position, and rotation speed, so that the cave returns to the centre of the screen. There are also keyboard controls to use instead of the mouse:

<Z>, <X> : Faster/Slower Rotation 
<R>: Reverse direction of rotation 
<Enter>, <Space>: Start and stop auto-rotation 
<C>, <V>: Rotate cave one step clockwise/anti-clockwise 
<'> , </>: Higher/Lower Viewpoint 
<]> , <[>: Zoom in/Out 
<U>, <D>: Set view to Up/Down 
<N>, <S>, <E>, <W>: Set view to North, South, East, West 
<Delete>: Reset to default scale, rotation rate, etc 
<P>, <L>: Plan, Elevation 
<Cursor Left>, <Cursor Right>: Pan survey Left/Right (on screen) 
<Cursor Up>, <Cursor Down>: Pan survey Up/Down (on screen) 
<Ctrl-N>: Toggle display of station names 
<Ctrl-X>: Toggle display of crosses at stations 
<Ctrl-L>: Toggle display of survey legs 
<Ctrl-F>: Toggle display of surface legs 
<O>: Toggle display of non-overlapping/all names 
<Ctrl-R>: reverse sense of controls 

A little experimentation should give a better understanding of how this works.

There is an auto-resizing scale bar along the bottom of the screen which varies in length as you zoom in or out. In the lower right corner is a compass pointer showing which way is North, and a clino pointer showing the angle of tilt.