I'm a Microsoft Technical Evangelist and I have developed a sample and free tool (no support/no guarantee) to help in these scenarios.
The binaries and source-code are available here: https://blobtransferutility.codeplex.com/
The Blob Transfer Utility is a GUI tool to upload and download thousands of small/large files to/from Windows Azure Blob Storage.
Features:
- Create batches to upload/download
- Set the Content-Type
- Transfer files in parallel
- Split large files in smaller parts that are transferred in parallel
The 4th feature is the answer to your problem.
You can learn from the sample code how I did it, or you can simply run the tool and do what you need to do.
