Thanks all, I even got a gong from Charlie Bates Astronomy project!
I've subsequently loaded a program called SharpCap which does a much better job of image acquisition, so fingers crossed for a better result next time
Dean, we did use Cal sky (and IIS Transit Prediction for Android), both are as accurate as can be and certainly within a few seconds in time an a few tens of meters on the ground. Our aim is to be somewhere on the centre line for each event to ensure we capture the event - and even better if that location is somewhere nice with a café!
Join the FB group if you want regular updates - there is a great event over Brisbane city tomorrow at 7:48 am, but weather is iffy.