Well, according to my "OutDated" Commander's Edition Vol III...
The Adromedends were bent on complete domination of our entire Galaxy.
Only after heavy losses by most races did they form a Coalition and ALL races united in "Operation Unity" and drove the Andros back with a 3 pronged assault, fighting all the way back the the Magellanic Clouds, the Andromedens Home space, where they finally defeated the Andros once and for all, again after heavy losses by all concerned.
The entire Operation Unity lasted 2 years.
The Andros have weapons that do massive damage, and the ability to "teleport" your ship (The Displacement Device), to practically anywhere they want, coupled with the powerful Tractor-Repusler beam, made them heavy with offensive firepower.
Weakness: Lack of decent Point Defense, mostly Ph-2s, supseptable to massed drones and fighters. Plasmas can do a real number on them also. Their Power Absorber panels (what they use for shields) can be hit and destroyed, causing them to explode with the amount of energy stored, causing further damage. But, they can channel that Absorbed power back into ship systems every turn, making them able to dissipate stored energy.
Played out the campaign once in SFB for over 2 months, never coming to the end due to RL.
I found Lyrans and Feds having the most difficulty handling the Andros, since they need to get fairly close to use their main weapons, the T/R beam is tremendous at closer ranges.
The satellite ships (DD and FF class ships, typically, a CA carried 2 FF and one DD) made fighting groups of Andromedens...interesting...
Gonna be hard to duplicate Andromedens effectively for OP...GL...