You're completely right about never, ever editting or adding to God's Word. What is needed however is to show people who have been brought up and educated to believe they are mutually incompatible that this is not the case.
It's a sad fact that if I questioned any of my Non-Christian friends about why they weren't religious the instant response would be:
"Well, it's that Bible, isn't it? Load of cobblers. Says the World was created in just under a week! Why'm I going to bother with something as outdated, out moded and misguided as that?"
So yes, there are MUCH more important things than worrying about whether or not Genesis measures up to our human experience and expectations, but it is also necessary to show that you can be a Christian and believe in modern science at the same time.
God Bless
Nick