@Sab First I would have to say both fog server and fog storage node have to be on the same version. The fog storage node doesn’t have its own database, it uses the fog server’s database. There could be schema changes in the database between 1.5.10 and 1.5.9.
Unless you change the storage group around, its not possible to capture to a storage node (in the default configuration). Only the master node in a storage group captures the image, then it replicates the captured image to all storage nodes. Both the master node and storage node can deploy images.
If I had to guess, I would think that in the storage group the nas fog server is not defined as the master node. If I think I understand what you did to configure this setup.
On the fog error screen it should print out the kernel parameters sent to the FOS imaging engine. There should be a filed marked storage or storage_ip, that will point to the fog server it will try to get the image from. Make sure that is correct for your configuration.