Controls? keyboard controls? Manual is useless if you aren't told how to control anything.

Not sure if you are still trying to play the game, but I found this for PC's and such:

The Commodore 64 only had two joystick ports, and its port of MULE did not support paddles. Thus, players three and four had to use a pair of keyboard keys during the auctions, and the joysticks had to be shared during the player's main turns.

The IBM port only supported one joystick, notwithstanding the IBM Game Control Adapter could support two joysticks with a Y-splitter and the IBM PCjr. had two distinct joystick ports. Unlike the Atari and Commodore versions, it did not require a joystick to play the game. If you did not have a joystick, the arrow keys could be used to control the player during his or her main turn. Only the main four cardinal directions could be used, the "diagonals", 1, 3, 7 and 9, do nothing on the PC keyboard. The PCjr.'s keyboard has no numberpad, only dedicated cursor keys.

For the auction phase, the keyboard controls for each player on the IBM PC are as follows :

Player - 1 2 3 4

Up - F1 W O ↑

Down - F5 X . ↓

On the PCjr., the keyboard controls are different, due to the differing layout of the PCjr.'s keyboard :

Player - 1 2 3 4

Up - W Y [ ↑

Down - Z B / ↓

There is a game crashing bug when selecting joystick control with four planeteers. The Alt key is pressed to determine which player will use the joystick. However, if players 1-3 use the joystick, the game will not allow you to press key to select player 4. Player 4 must use the joystick in this case.

This game was designed for the IBM PC 83-key keyboard. On the 83-key keyboard, Player 1's auction up key, F1 is above the down key, F5, by one key, just like the keys for Players 2-4. On a 101-key keyboard, F1 is three keys to the left of F5. This arrangement simply does not work well with three other people.

The keyboard handling takes some getting used to. The Enter key corresponds to the joystick button. When doing anything requiring a button press like selecting a land plot, beginning your turn or installing a M.U.L.E., it is best to hold the button down until the game acknowledges the input.

The Alt key functions essentially as a speedup key in the game. It can end auctions after everybody has bought and sold what they can. It can bypass the summary screen and the chance animations.

The Esc key acts as a pause key. Unfortunately, it will cause the game to freeze on a Tandy 1000 90-key keyboard. If you are going to play M.U.L.E. on a Tandy 1000, I would advise using the joystick and setting the speed machine to slow (if an EX, HX, SX or faster) at boot time. On the Tandy 1000 90-key keyboard, the Esc key is right below the F1 key, making it too easy to press if you are controlling Player 1. The composite colors on a Tandy with an RCA video jack (TX or earlier) will look different than on an IBM PC with a CGA card.

Finally, the game can be saved in progress by pressing Ctrl-Q. This does not appear to be a feature of the earlier versions.