LaunchConfig with Cloudformation::Init

gistfile1.txt

"LaunchConfig" : {
            "Type" : "AWS::AutoScaling::LaunchConfiguration",
            "Metadata" : {
                "AWS::CloudFormation::Init" : {
                    "config" : {
                        "files" : {
                            "/tmp/boot-strap-nat00.sh" : {
                               "source" :  { "Fn::Join" : ["", [
                                   "http://", { "Ref" : "AWS::Region" }, "-development-appname", ".s3.amazonaws.com/path/to/boot-strap-nat00.sh"
                               ]]}
                            }
                        }
                    }
                },
                "AWS::CloudFormation::Authentication": {
                    "rolebased" : {
                        "type": "s3",
                        "buckets": [ { "Fn::Join" : ["", [ { "Ref" : "AWS::Region" }, "-development-appname" ]]} ],
                        "roleName": { "Ref" : "IAMNATROLE" }
                    }
                }
            },
            "Properties" : {
                "AssociatePublicIpAddress" : "True",
                "KeyName" : { "Fn::Join" : [ "", [ { "Ref" : "AWS::Region" }, "-development" ] ] },
                "ImageId" : { "Fn::FindInMap" : [ "RegionMapNat", { "Ref" : "AWS::Region" }, "AMI"]},
                "IamInstanceProfile": { "Ref" : "IAMNATROLE" },
                "SecurityGroups" : [ { "Ref" : "SGnat" }  ],
                "InstanceType" : "m1.small",
                "UserData" : { "Fn::Base64" : { "Fn::Join" : ["", [
                    "#!/bin/bash\n",
                    "set -e\n",
                    "set -x\n",
                    "yum -y update\n",
                    "sleep 3\n",
                    "yum -y update\n",
                    "easy_install --upgrade boto\n",
                    "# Download our bootstrap file\n",
                    "/opt/aws/bin/cfn-init -s ", { "Ref" : "AWS::StackId" }, " -r LaunchConfig ",
                    "    --region ", { "Ref" : "AWS::Region" }, " || error_exit 'Failed to run cfn-init'\n",

                    "chmod u+x /tmp/boot-strap-nat00.sh\n",
                    "/tmp/boot-strap-nat00.sh\n"
                ]]}}
            }
        }