If I can chip in with a couple of things. Once you have sorted out a DCCache with the level of store content in that you need for your project be very careful not to open your CAW file with the wrong DCCache in place. I did this once, after a reinstall and I had missing items from my current version of my CAW file. Fortunately I had a backup copy on an EHD.
Secondly Rflong has a fantastic tutorial on levelling terrain. Often the terrain looks flat but it isn't. I would send you a link but I am on my tablet. If you Google it, it should turn up.
Good luck in getting CAW working again. It will be lovely to see how you progress on your project.
Betty