Correct way to image a device

Hi,
I have some problems (-34 and/or -28 errors) imaging correctly devices that
already are in my zone.
I have to delete them from the zone then register the back to the zone
manually.
I would like to know what is the best and working way to do an image of a
device before pulling it to other devices.
1- How to do an image with ZCM agent in it for existing and/or new devices
2- How to do an image without ZCM agent for existing and/or new devices
We don't use sysprep.
Should I use it ?
Thanks.