There's also the Dada Mail Manual that comes with Pro Dada. It's geared more towards your average user. The majority of the manual is a walkthough of the various list admin control panel screens and what they do. If what you're look for is a Program Manual, that's it.
The majority of the time, we solve most every problem you can think of by upgrading your Dada Mail and kicking the proverbial car tires of Dada Mail. It's the easiest and cheapest (for you) way to get things rolling again.
We hate to admit it, but being paid to hack on code does lead to fast and incredibly amazing results. Please contact us via email with your ideas.