You can change the single player campaign settings from Domination mode (capture points) to Cruiser Clash since the game launched in the options menu. Glad that your tech issues are resolved! I've had a similar problem on my ultra wide where everything was stretched and there was no supported resolution for it. Managed to make some changes to the configuration files and fixed that problem.
Managed to win my first multiplayer game in a mirror match between the Tau Protector Fleet. I brought two Kroot Warspheres to the match, a demirug bastion, and some smaller ships. Opponent went in all in on T'au Cruisers and demirug bastions. Quickly got the advantage simply charging up the field and cornering my opponent to keep him off of the strategic points.
Everything else has been loses of some varying degrees. I can do a lot of damage, but am having trouble keeping my fleet alive toward the main game.
I was surprised because I think I've formulated a method for the Craftworlds. Instead of attempting to micromanage and split up the fleet, I think craftworld ships work better as a single close knit formation that can support one another. Charge up the battlefield, establish good dominance with the capture points, then blitz your opponent with some brutal hit and run attacks.
3-4 Eldar Torpedo boats unleash their salvo at the same time to create a huge blanket that's difficult to escape from. Lay down some plasma bombs, warp in the opposite direction and zoom out of there. Turn back once thrusters are available again, full speed into the opponent and use boarding parties for each vessel on a ship that I want to depopulate into a drifting hulk very quickly. Have a couple of fighters to counter other fighters. And just recycle that process, all the while using the runic targeting mode and the flagship buff that improves it, to lay down some serious firepower on the way in.