LANDER.BA isn't a very sophisticated program.  It is loosely patterned
after other lander programs.  To play, you select the amount of engine
thrust (from 0-9).  The amount of thrust will remain stable until you
change it or you run out of fuel.  It is not necessary to shut the engines
down when you approach landing; in fact, that may lose it for you.
   The object, of course, is to land safely and softly.  As you approach
the lunar surface, gravity increases -- so you must use more thrust.
   To the "Play again?" prompt, you answer Y or y, or if you are using the
number pad, "1".