I come to aid thee in thy tribulations! Ensure all off-axis turrets face forward. This way, you can have uvec be 0,0,1, and you don't have to bother with making the fvec values negative.
Easiest way to defeat the enemies. Also, before you apply the turrets, record what the rotation about the forward axis is (I dunno what program you're using, so I can't tell you which axis for sure). You'll need this in order for your LRTrigBeams to acquire target successfully.
Huh... I wonder.... can you mount a multipart gun on a rotating subobject? I must try this, for great justice.