First of all thank you very much for this awesome website.
I think there is a mistake in DMux8Way.cmp. In the file, sel is an array of 2 bits, when it should an array of 3 bits (as you need to make choice between 8 different sources of output).
In particular, these lines don't make sense at all!
| in | sel | a | b | c | d | e | f | g | h |
| 1 | 00 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 00 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 |
How can the same value of sel yeld to two different results ?