Do you get any of customization log files inside the guest OS (C:\Windows\TEMP\customize-guest.log, C:\Windows\TEMP\vmware-imc\toolsDeployPkg.log)? If so, please attach those.
What version of VC do you have?
Also please try to run with some basic customization script like
echo > C:\test.txt
to see if that solves "Invalid value '' specified for property vCloud_CustomizationInfo" error.
Also please attach stacktraces and messages around the failed operation from $VCLOUD_HOME/logs/vcloud-container-debug.log.