Hob!
Re the query about cup-markings down South. They're certainly few & far between, but that aint to say they're not there. A rather good example can be seen at Fyfield near Avebury, where as many as 23 simple cups can be seen on one of the rocks (SU 135 715). Cup-markings were also found a stone in a round barrow at West Harptree in the Mendips. I'll stick a post of them on TMA later on. Aint gotta picture of the Mendips stone, but there's one somewhere of the Fyfield carvings in an old archaeology mag stuck in one of mi boxes.
Paulus