"About the turrets: If you reference "caduceusturret" you have to have either the caddie oxp installed or have to setup a subentity entry in shipdata with exactly this name.
In stock Oolite however is a generic "ballturret" subentity which anyone can use. Either way you have to adapt the position and orientation of the new turrets for every other ship, so they are placed on the Hull and not in the Hull or floating in space around your ship."
I did put 3 turrets about 30m infront of my ship for fun. Distracting, but fun.