Layout
The design of the Nostromo, and really any keypad, is to replace the keyboard by better providing access to an adequate amount of keys available to the left-hand (sorry lefties). The Nostromo begins with a large arc piece which supports the wrist and positions the hand into an arched-claw.

The face of the keypad has three rows of keys, the top two with five each and the bottom with four, sharing the last spot with the top half of the scroll wheel. When the hand is in the arched position, the fingers should end naturally at the middle row, 07, 08, and 09. The 08 key is the home key, marked with a ridge so you can find it without looking much like the F and J keys are on the normal QWERTY layout. The idea is to be able to navigate the Nostromo without taking your eyes off the screen, and knowing that you're middle finger is at the 08 key also tells you that you're on the middle row, and you're index and ring finger are on 09 and 07, respectively.

Extending your fingers flat should more than reach the top row, and pulling them back a little allows easy access to the bottom row. The scroll wheel, for me at least, was always comfortably available with the index finger regardless of which row your fingers are currently working. The thumb stays stationary as well, resting on the analog directional pad. The knuckle/shaft of my thumb rests slightly on the 15 key below, making it easy to press quickly. Under this key is a three-LED indicator for which keymap  is currently selected, eight available and achieved by using all, none, or any combination of a blue, green, and red light. Above the directional pad is the 16th and final key, an unmarked circular button. Finally, on the bottom of the Nostromo is a quick-access switch to turn the LED underglow on and off.