Question 1: Yeshayahu 45:7 describes the fact that Adonai created rah. Bereshit 1:31 tells us that Adonai did watch all that he had made and saw that it was tov me'od. If something like rah is created and one of the components of that which is called tov me'od then.. What is rah good for? (why was it created in the first place?) (How does rah give us free choice? doesn't it attracts us to doing bad things?)
Question 2: Why was it forbidden to take knowledge of rah if HaShem created rah; or created the tree of knowledge tov v'rah? Why wouldn't HaShem allow the first human beings to take knowledge that which is tov and that which is of rah? (why else does this verse says: 'knowledge tov V'rah? - tov AND rah). Because from a human view it would seem that this knowledge/understanding could help us to do the good/right thing and refrain from doing the bad thing.