Thank you for providing the file for testing. However, I have tested by importing and exporting the file using our Demos. On the linked screencast you will see the behavior on my end. The file is correctly exported without any issues. Please let me know if I am missing something. May I ask you to test the same file in our Demos and let me know about the behavior?
I will appreciate it if you could isolate the issue in a runnable sample and send it back to us. Thus, we could investigate locally and advise you further. If it is more convenient for you, you could modify the Dojo example linked here.
Looking forward to your reply.