As far as I know, CC3 only exports BMP and JPG, and it only wants to export 72 dpi. I think it can export higher resolution, but poorly and takes a long time to export - at least in my experience. It does not export PNG. CC3 native file format is problematic. I run a digital print shop and run CC3 just to print CC3 native files, though I prefer 200 dpi JPG at least.