hi mick, i don't have experience with your machine, but i believe that you should talk with your okuma dealer about fixture tracking; OO88 i believe

Machine datum center off the pallet with b axis center of rotation. lang quick fit tower attached on center
i don't know how your towers are set, but you should not lose time, trying to have the tower middle axis aligned with the b axis, buy only it's sides paralel to the xoy system ( this should be default, as long as T grooves are aligned bettween pallets, and B encoder origin reflects a position where the grooves are paralel to X or Y axis ); is enough to put some rods on the tower, and use feed skip ( or probe them ) , so to detect their height and automatically load the pivot distance & orientation & maybe offsets; this trick shaves in-machine preparatory times

machine came as turn key package, sort off
turn-cut spec, like the moon arround the earth

None of us really have any experience with this type of machine
your okuma dealer should perform a basic instruction, for a few days; talk with them about your needs, in advance, so they will came prepared; i am saiyng this, because " turn-cut, oo88, feed skip, probing with custom macro ", are not comonly used, and not everyone has experience with them

when it comes to pallet number detection & zeroing, with feed skip & encoder calibration ( = cheap ) you can do same stuff as when using a program generated by renishaw plus ( = expensive )

is good that you know how things work on the heidenhain, so to try and replicat that in the okuma; are these available on the heindenhain :
... skip function
... sending offsets and zeros from outside the machine ?

you can really boost productivity with that pallete horizontal center / kindly