I'm a sales specialist for Sears Fencing. I have sold fencing for the past 4 years, and you are right you will run into a lot of difficulty. It takes years of experience to learn how to install clf. When running down hills you may need to put a term. post at the top and bottom of hill. This will keep the chain from buckling. You also have to set posts level and cut with the run of the land. Be sure to cement each post into the ground. After your post set for a few days you can now run the fabric. Be sure to pull tight with a come a long.
Maybe you would like a Sears Specialist to look at your fence for help..