Working with CS6 InDesign files provided by others. Odd things are happening when I open them in my CS6 and also in CC 2014. First, some text that had been horizontally centered in text boxes (in the original) now appears off-center and aligned at the bottom. I appear to have the same fonts as the original author of the document because I didn't get a missing fonts notification, so the realignment doesn't seem to be caused by font substitution. Second, graphics that were at the back in the original version, overlaid with captions, have moved to the front and now block the captions. Third, graphic boxes that previously had no runaround (text wrap) properties now have them, and surrounding text is getting pushed out of alignment for that reason. Any ideas about why any of these issues are occurring?
Are you sure they were CS6 files to start? Direct conversion of legacy files can sometimes do strange things.
I'd recommend exporting to .idml and then do whatever you need to fix them. See Remove minor corruption by exporting