I won the level (on Normal).. (took about 6-8 hours, and I had 68bc left in my account

. -> Here's what I did..
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The worst part was that I had medium hulls, plasma weapons and 12 turns to make my best offensive ships. They had four battleships running around my territory. My allies refused to go for the goal, and the DLords had to go through my territory to get to my allies. The result was that I had no military and my Allies had a ton of troops (in their own territory).
The DLords did force the Drengin to surrender to the Yor.. Which, when I finally got ships over there, It had quite enough DLord fighters and destroyers.. Not much in the way of Yor military.. Could have ended the game if I didn't have Yor-fighting ships guiding the first wave of transports in.
It took twice, but I won. The first time, I rushed technology and manufacturing buildings.. I gave up when I knew I didn't have the economy to pay for the maintenance.. The second game I only rushed the first couple of research levels, then branched out and made sure I had a taxable population.
The second time, I had a planet which had a 700% manu bonus square and a 300% manu bonus square. I put my manu capital on the planet.. It was costing me 200+ credits/turn to run (and received only 42 in taxes..), but would produce 300-pt ships in 2 turns.. Sometime around 20k (reserve cash) I decided to plasma up my cargo hulls and go after the DLords.. I would take 5 of these beasties, beat one of the two sentried battleships down to 2hp, and he'd run away long enough for me to build another 2 ships.. Then his 'buddy' would come down and we'd repeat the process.
What really seemed to change things was getting Warp Drive.. With my impulse engines, I had a speed of 5, like the battleships. They would follow my ships into my allies' territory and my allies would beat them down with the numbers they had built up (from doing nothing).
For advice, I'd say that you never want them to get a second planet. I had AndersonA, and he'd send a ship to clear the planet of defenses about 5 turns before the transport. The attacker would leave just in time for me to put in a defender. I was also able to generally keep a population of 8000 on the planet, which would be reduced to 4500.. I found out that anything less than 5000 population would cause me to lose it. So, when I didn't get a defender there in time, I had safety population, or vice-versa.. I was able to hold it until about 4 turns from the end of the game (when I couldn't have cared less).
..And, Give techs freely to your allies

. (Like, give them something every 10 turns, or so..)
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