I'm playing the DA Campaign with the Ultimate Edition (TOA 2.02, painful). I found the winning strategy to be much the same as other DL Scenarios from the DL Campaign.

Start with +2 speed.

Grab several colonies quickly.

Put some transport hunters in play early. Speed 8, lots of sensors, small weapons, small defense if any.

Lead DL warships on a wild goose chase, pick off the transports.

In my game the main stratigic contestwas Vizzard. I spent the whole game protecting it, the DL spent the whole game trying to sneak in a troop transport.

I destroyed a colony for the first time in my GalCiv2 experience. There was a habitable planet near Dither. The Iconians colonized it and soon the DL took it. I took it back but couldn't protect it so I destroyed it.

I took Dither in July 2229 with a fleet of 12 tiny fighters (8 beam attack, no defense) followed by 2B troops.

Unlike earlier DL encounters, the DL didn't magically detect all my starbases and destroy them.