Sadly, still true. The system was built for a co-op server, so that one player would pilot the carrier and one in the tower to disconnect when the defenses are needed.

I thought the guns and turrets couldn't fire when it's docked, is that still true?

Sorry for the late response. Not 100% sure how to respond. There are landing gears in the front of the tower to latch the ships together. If you watch the aft area of the tower, while docking, you will see 3 gray colored squares on the Gaia that match the tower's 3 aft pipes. When both ships are level, you should just be able to go straight down to dock (default is "C"). If the elevator in the center of the bottom bridge area is in line, you will be able to go down the elevator directly into the Gaia's aft hangar area.

how to connect the tower with your ship? with N it doesnt work