1. EC2 `InstanceNetworkInterfaceSpecification` is slightly incorrect comparing to https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-ec2-network-iface-embedded.html. Fields such as `Ipv4Prefixes`, `Ivp4Addresses` are optional according to documentation. `Groups` are actually spelled `GroupSet`. 2. Running `runInstnaces` with `NetworkInterfaces` supplied in request lead to exception from AWS ``` Interrupted AwsServiceError: UnknownParameter: The parameter networkInterface is not recognized [Request ID: 4453910d-60c4-4c8a-8edb-169631ff8fdf] ```