There aren't many multiplayer replays for the latest version of Entrenchment, since most of the multiplayer community has moved on to Diplomacy. There were some good multiplayer Diplomacy replays posted up by a few players recently, but those won't help you much. Keep in mind that auto-record is enabled by default, so you can review your own games and see what your enemies did.
The most likely issue you're having is colonization. The key to a strong early-game is rapid colonization, which usually employs a few tricks to speed things up. A very common trick is to kill the Krosovs in the militia, then colonize the planet and build a turret or two to destroy the remaining militia. If you do it right, this can be done very quickly (use scouts instead of light frigates, they're faster and they have bonus damage against Krosovs) and without casualties. Against asteroids, you can actually do this with just a lone colony frigate. You can complete the turret quickly enough to kill the lone Krosov (place it right up against the planet, and the Krosov won't be able to relocate out of range) and take control of the planet.
Hope that helps!
PS - try posting in the Sins Strategy section next time. I'm pretty good about ensuring that every question that gets posted there gets an answer, but I might miss you if you post in general PC gaming!