Thread title.
As a fan of Stephen King, if changes did bother me, I'd be bothered a lot
I don't really care, unless they either leave things out or change things for baffling reasons, or hurt the "integrity" of what they're adapting. I.e. I hate Batman killing folk in the DCmovies, but I don't care about character differences in the Arrowverse.
I hate that the new IT movie pretty much gave all of Mike's character to Ben, and I also hate that Beverly was effectively turned into a damsel. But I don't care about things being added or left out.