Using contiv 1.1.9, the install/k8s/install.sh script attempts to extract netctl from the contiv/netplugin:1.1.9 Docker image: https://github.com/contiv/install/blob/master/install/k8s/install.sh#L307
The referenced path, /contiv/bin/netctl does not exist in that image, and therefore install fails with the message Extracting netctl from netplugin container Error: No such container:path:
The correct path appears to be /go/bin/netctl