Official website

This legendary mod may not be adapted for the singleplayer campaign, but it includes a vast number of ships, bridges and features for instant action and multiplayer.

so is this still the de facto mod to play multiplayer with?

How do you install it?

Just extract the mod into your main Bridge Commander folder and overwrite everything he wants. Just to be safe make a back up from the whole game, so you can switch back to the main game.

How to install in on the MAC version?

Yea can I get some help I installed Star Trek bridge commander using Gog galaxy the game works fine but when I try to play reamsterd or Kobayashi Maru

According to the author the Legacy mod is 99% stock, Only the Akira has been changed and they left the old .py file there if you need it. Its without doubt the best mod for single player IMO. The one thing that is bad is the explosions ánd I have fixed those myself and made the stock plasma leaks better now it now looks just scenes in Wrath of Khan so very pleased with it.

KM is fun but unbalanced and unstable and as you said not good for the campaign.