Ah ok so i use the lens settings tab to specify non-global parameters for my nadir shots then make sure fov is ticked in the optimiser advanced tab for those shots, then run the optimiser and align again.
Great, can't to try (with fingers crossed!).
Listen, i really appreciate your input. You guys have really gone out of your way to help. You've really helped me through a glut in my learning curve and i am excited to put it into practice and develop my pano skills. I will remember to re-pay the favour by helping someone else in the future. :)