I think that the Na had a double set of diamond wires and some of the extra metalwork on the mast may relate to this. Us europeans didn't need a longer mast to go fast so I will leave it to some of your brethren to fill us both in on this one!
Otherwise it may be the result of spinnaker experimentation.

the big cleats on the front beam that face foward and outboard are for jib sheet barber haulers. They are to change the sheeting angle when sailing downwind. Again, look at the rigging manual

The gap in the beam straps does not look normal, but should be ok as long as the straps are in good shape.