Great question, Resha! I know that from my own experience as an evolutionist, it has been difficult (to put it mildly) to attempt to reconcile the physical fact of a long evolutionary history with the much shorter, genealogically laden, Hebrew representation of human history we find in the Bible. So, for me, the main issue has been dealing with the main bug-a-boo of "if Adam didn't exist, then what was Jesus needed for?" and related kinds of questions.
Other than that, I'm busting my chops to try to think of some other major theological hurdle I had to jump over in order to accept Christianity and the Bible as God's Work. I guess there was also the question of whether and how we have something like a soul ... and all that.