Quick Answer:

The circular button on the right side of the button panel is a four button combination pad, and the tall button to the left of that is a two button combination pad. Both are programmable just like any other button on the device.

Further Details:

Four button combination pad:

This pad contains four buttons; one at the top, left, bottom, and the right. You may find it handy to program this pad like a directional pad for controlling the pan and tilt functions in your software application.

Two button combination pad:

This pad contains two buttons; one at the top and one at the bottom. You may find it handy to program this pad for controlling the zoom in and zoom out functions in your software application.