Back again. @Impish -It does run on my mac though what I find odd is that I can only see how the terrain is affected in the preview window or if I do a quick render. Is that how it behaves on all machines ? I'm going to go play with it some more now. I've not tried any python script in Vue before so not familiar with the thing at all.

" Try and be nice to people, avoid eating fat, read a good book every now and then, get some walking in, and try and live together in peace and harmony with people of all creeds and nations."
-Monty Python