I personally believe that most of Muslims agree that Quran is 100% perfect and is 100% from God, but they only differ in its interpretation. Some take it literally, some take it metaphorically, and some mix both, meaning to believe that it contains both.
It's REALLY, REALLY helpful for me to hear from you that Muslims view the Quran differently. Some take it literally, some metaphorically, and some interpret it. This makes intuitive sense to me, but you're the first Muslim I've talked to, who's said it - thanks!
But if fruitful discussion of the matter is to be had, we must first build a mutually understandable and acceptable vocabulary and concepts. And the idea that such problems are caused chiefly by the Quran with no significant influence from political, demographic, historical and military factors is one that I have a very hard time taking seriously. It just doesn't fly with what I know of Muslims.
I've thought about this a lot, and I agree, it IS complicated. On the one hand, as has already been discussed, the world's billion-plus Muslims live all over the world and have been brought up in countless different cultures.
On the other hand there are examples of Muslims - from across the world - thinking and acting with some degree of unison. Several years ago the Pew Research organization did a world-wide poll of 38,000 Muslims across many regions, and on some questions Muslims around the world agreed (to a large extent). Another example was the unfortunate incident of the Danish cartoons which triggered violent reactions from Muslims from all over the world.
This is all to say that while it's certainly true that Muslims are a diverse group, there also appear to be some common beliefs.
I'm not at all stuck on the idea that these common beliefs come from the scripture. But I'm curious to understand, if not from the scripture, then where from? Because as has been mentioned, politics, and economies, and cultures vary widely.