What format is being used for export? Or are you attempting a direct export to YouTube, Google Drive or the like?
The issue likely can be solved if you share your project. It's easy, takes but a minute or two and can be private.
Here's how... http://nch.invisionzone.com/topic/23659-tips-for-getting-help-on-this-forum/
If it contains sensitive material link it in a personal message (PM). Click the envelope above. It won't be passed on or retained. Use FILE|SAVE PORTABLE PROJECT AS, not simply SAVE PROJECT, and don't forget to share it.