These images show the next stages I am progressing through. I have heightened the building, added three steps to the front taking the front vectors of the bottom step and moved them to create the causeway. I then used a duplicated cylinder with a deformity at the top (under the causeway) to act as the causeways supporting struts. A slight rotation on each pillar should be interesting when the scene is lit and nearer completion.
I then deformed the buttresses to give a more rock-like appearance. I'm not happy with the two smaller buttresses at the front they just look odd at the moment, but the remaining three look pretty strong. I have a slight concern that I have deformed these smaller details to such an extent that i'll need to start afresh but ho hum.