This morning when I took a look at the file the deep edge just over the clouds bothered me. Keeping it even with the top edge of the board used up a lot of valuable depth real estate, which I would need to create the waterfall. The depth of the cut would also be problematic as the bit I intended to use simply wasn't that long. I could do a maximum of 1.5" on that cut. It needed to be fixed.
The solution was to crete the clouds as a separate relief, then dish it in using an oval vector ) as I had done with the starburst background.
Once I had floated the relief to the right height I them merged then together using the 'merge highest' command.
The end result was a file that could easily be handled with the bits I use. It was now ready to tool path and send to the router at last.