You may not be able to export the config file because you've not set a base PAN config file.
Please refer the following link to learn more about using Expedition and importing your base configuration.
PS: You'll need to merge your configuration (Cisco ASA + Base config) before you can export it to your target firewall. The Expedition User Guide v1.2 has all the details you would need.
The typical migration workflow is:
Please refer to the Expedition User Guide for detailed instructions along your configuration migration:
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