This is caused by Spotlight running in the background, which eats up all the memory and causes the agent to crash and not function properly. To see if you have this problem run this command while in automation after you tried to capture or deploy an image:
df -h
You will see that a lot of the shares are at 100% which is why its not working properly.
To fix this issue we need to disable spotlight before you capture the netboot.
For OS X 10.5 and up:
Move these two files to another safe location and then reboot your mac
/System/Library/LaunchAgents/com.apple.Spotlight.plist
/System/Library/LaunchDaemons/com.apple.metadata.mds.plist
We are working on getting this fix into a future release.