I want to Panelize and merge multiple PCB jobs together using PCB Preflight. However when PCB Preflight completes the job I received an email leading me to – no gerber file. Why?

Thanks for your question and sending the sample matrix blob.

When viewing your matrix blob, your matrix file does not tell PCB Preflight to export gerber files.  Please add the following to the end of your matrix file and resend that matrix blob to PCB Preflight.  It will now generate the Gerber files you require and provide the URL links to download in the resulting JSON file.

Here's more information about the EXPORT_GERBER array, https://numerical-help-guide.s3.amazonaws.com/matrixfile/html/matrix-export_gerber-array.html

Here's tutorial movie showing me add the EXPORT_GERBER to your matrix file, zip everything, and upload that matrix blob to PCB Preflight for manual processing.