I'm playing this game for a couple of days now but I still haven't figured out to fire missiles.
Whenever I press the middle mousebutton I hear some sort of error beep.
And I have a cl 1 missile launcher and cl 1 Swarm missiles.

Is there anything I'm missing? Like in Wing Commander you need to press "L" to lock on the target or something.

edit:
Nevermind, I figured out that a missilelauncher only works if it occupies a weaponslot, that's rather dissappointing as it takes quit a while before you have 3 weaponslots.

Another thing that still eludes me though is that the left and right arrow keys do nothing, while they should adjust weapon and shield recharge according to the manual, it works if I do it with the mouse but in the middle of combat that is a pretty awful way of doing it.

You have to buy an equipment item that allows you to swap energy between shields and weapons, same for transferring energy to front and back shields. You can also try rebinding your keys if there's some bug.

BTW, unfortunately you can't use multiple missile launchers at once.

The slider on the top left is different from the reassigning energy via arrow keys. The latter only works when you have a certain item installed in your ship.