Okay, sooo, I am having this issue as well with responsive theme. The only thing I have in the child theme is the child style.css and my customized front-page.php. I only have a few changes to the front-page.php that need to be maintained. Currently my changes are present in the parent theme, because I directly edited it (this is why I am creating a child theme because I don't want to lose my changes when I update). Anyway, before I update responsive theme I want to make sure my child is displaying properly, and it is not! When I activate it, all my widgets are screwed up, moved around, and content changed. I don't understand what is happening since it should be calling in the exact same thing that is showing in the parent perfectly!
I tried adding the @import url(..'responsive/core/css/style.css'); line as suggested in this thread and it didn't make a difference. Any other ideas!?? need help :/