On the last image John you have a fantastic rain free updraught base (RFB) covering a large area, that's the inflow part of the cell which sucks air in and upwards into the base, it's also the location where funnels and tornadoes can form. There's great slolid structure under it too, nice one. It should have been calm when that passed near. The large area of rotation was probably due to a convergence zone, there where several of them in E and SE NI that day which is why TORRO had a tornado risk issued. The wind fields meeting from two different directions must have been close to your location, that explains the rotation and the big storm. Hope this helps. Good to know someone else was going imaging the amazing sky that day.