As I am still trying to figure out the basics of Casper and OSX in general I am trying to work through the flow of creating a USB boot stick and the eventual OS image. Having never done any of this before I have taken advice from these forums and others. So far, I have had... moderate success.
Is there documentation somewhere on the best method for creating a restorable image that can be placed on a USB drive to be used for Casper Imaging?
I have used AutoDMG to create a DMG file from latest Yosemite installer. Have then taken the DMG and ran it through AutoCasperNBI, ticking the 'Create A Restorable DMG' option. We are currently running Mountain Lion across the board and ACNBI never finishes, so I ran it on a factory Yosemite machine and it pops out a restorable DMG, as it should. However, imaging with USB created from this continuously prompts that the Casper server it is connected to may not be the true Casper server. It seems to be asking for a certificate of some type? I have watched ACNBI run its process, it appears to grab this from the Casper server that I defined in the initial setup. Has anyone experienced this? Is there a way to make it stop asking? It has to be acknowledge by clicking ok or cancel and stops the build while waiting for an answer. I will grab a screen shot when I can. Again, is there a better way/process for creating the image for the USB?

