snapshot - not producing the snapshot_manifest.txt

Hi Guys

I'm trying to migrate over my site from buildhq to and im using snapshot.

I've got the snap shot being uploaded to drop box, i then move it to a public folder, then imput the file and it comes up with the doesn't have the manifest file, i then looked into the zip file and its not there, i've done a few snapshots and still no luck can you help please