[kubernetes] Malformed KubernetesCluster.yaml causes upload error

Environment:
-Host Ubuntu 14.01
-Python 2.7.6
-latest DevStack (on single VM)
-Murano setup as described in http://murano.readthedocs.org/en/latest/install/index.html#installing-and-running-the-development-version

Problem:
When trying to upload the KubernetesCluster app, zipper content of
https://github.com/stackforge/murano-apps/tree/master/kubernetes/io.murano.apps.docker.kubernetes.KubernetesCluster
via the Murano web interface, the attend failed. The UI shows an error "The form cannot be submitted".
All other apps from https://github.com/stackforge/murano-apps/tree/master/kubernetes
can be uploaded without problems.

The Horizon log (attached)
"io.murano.apps.docker.kubernetes.KubernetesCluster\\" from package: Unable to load class definition due to \\"mapping values are not allowed here\\n in \\"/tmp/tmpY2h0I8/Classes/KubernetesCluster.yaml\\", line 70, column 45

points to this section in the YAML file:
"- If: $.nodeCount < len($.minionNodes):"

The upload succeeds when removing the ":" from the end of this line.