Using agent-config.yaml with DHCP network mode (i.e. without 'hosts' property), throws this error when loading the config-image: 
load-config-iso.sh[1656]: Expected file /etc/assisted/manifests/nmstateconfig.yaml is not in archive

4.14 (master)

100%

1. Create an agent-config.yaml without 'hosts' property.
2. Generate a config-image.
3. Boot the machine and mount the ISO.

Installation can't continue due to an error on config-iso load:
load-config-iso.sh[1656]: Expected file /etc/assisted/manifests/nmstateconfig.yaml is not in archive

The installation should continue as normal.

The issue is probably due to a fix introduced for static networking:
https://issues.redhat.com/browse/OCPBUGS-15637
I.e. since '/etc/assisted/manifests/nmstateconfig.yaml' was added to GetConfigImageFiles, it's now mandatory on load-config.iso.sh (see 'copy_archive_contents' func).

The failure was missed on dev-scripts tests probably due to this issue: https://github.com/openshift-metal3/dev-scripts/pull/1551