Just phoned S.O. tech support (reply to my email arrived during call - typical). Phone picked up really quickly, polite friendly chap, no flannel.
This is not a problem they have seen before. There is no way of rolling back to the previous firmware so they recommend doing factory reset from recovery menu (which I have already tried numerous times).
If that doesn't resolve problem, return to reseller (Maplins) or complete an RMA form and courier the unit to their HQ in Harrogate.
Before I do that (this evening) - has anyone else on firmware v1.02 experienced their Scroll hanging before the 'Welcome' screen?