There is a workaround for Puzzle 16, if you have v1.00.03:

You need to wait until the ghosts are not there, move the sun disk out of position, then wait for a bright sunbeam to appear again and move the sun disk into the correct position.

Of course, you will probably want to obtain the latest version, too. Since you have the Mac version of the game, and you don't have your order number, the best approach is to submit our Support Form and explain the situation exactly as you have done here. Make sure that you provide the email address you used at the time of purchase, or the record of your purchase may not be found.

I'm going to change the instructions for obtaining the latest Mac version, since it appears that Arthur is no longer monitoring the special email address he set up after 1.00.04 was released.