I've posted about this earlier but thought it was worth another try.
Using Premiere CC on a Mac Pro (with Mountain Lion and Quadro 4000 Cuda card) - when in a ProRes timeline (whether it be 422 or LT), and trying to export to ProRes (whether "use preview files" is checked or not), Premiere consistently hangs on export whenever it hits a graphic file (tiff, psd, etc) or a Premiere generated title. If I export into another format (h264, etc) - it exports fine (just takes awhile).
In Premiere CS6, "use previews" never worked with ProRes, but you could still export to ProRes - it just didn't use the preview files. Now with CC, you can't do either - at least not if you are using any graphics files or titles. If you're just using video clips in the timeline, then it works fine (using previews or not). I've tried this on 2 systems and have found other users on these boards as well as the Creative Cow forums that are experiencing the same issues.
Being able to export with previews was perhaps the biggest reason I upgraded to CC, but instead I feel like its taken a step backwards (at least on a Mac in a ProRes environment).
Is anyone from Adobe listening??
Since this is an export problem, you'll probably get more response on the AME forum. At the very least, staff members who visit that forum are more likely to know if this is a known issue.
What are the dimensions of your still images and, for that matter, of the PPRO titles?
If you have GPU acceleration enabled, please try encoding with it switched to Software-only (in Premiere; there's no switch for this in AME.)
Still images are 1920x1080 (same as my sequence). Whether its a PSD or TIFF it doesn't matter. Same issue. The PPro titles are also 1920x1080.
I have a Quadro 4000 with CUDA acceleration. I have tried exporting both ways (with GPU acceleration enabled as well as Software-only mode) - still the same issue.
I'll check the AME forums as well. Thanks