As we mentioned in an April blog post, one of our recent Cloud Files improvements allows us to quickly add support for additional headers. We can turn around your requests for new headers much faster. Based on your feedback, we not only added the suite of CORS headers but also added support for Content-Disposition. Here are your new headers:
Keep communicating and letting us know what headers you need via our Product Feedback forum. If you have any questions about these new headers, just let me know!