Amazon web services AWS opswork云形成无法导入

我正在尝试按照以下指南为Opswork VPC导入云形成模板：

我试着导入，但它一直告诉我

The following resource types are not supported for resource import: AWS::EC2::VPCGatewayAttachment,AWS::EC2::Route,AWS::EC2::SubnetRouteTableAssociation,AWS::EC2::NetworkAclEntry,AWS::EC2::NetworkAclEntry,AWS::EC2::NetworkAclEntry,AWS::EC2::NetworkAclEntry,AWS::EC2::NetworkAclEntry,AWS::EC2::NetworkAclEntry,AWS::EC2::SubnetNetworkAclAssociation,AWS::EC2::NetworkAclEntry,AWS::EC2::SubnetRouteTableAssociation,AWS::EC2::SubnetNetworkAclAssociation,AWS::EC2::Route

有人知道为什么吗？

以下是当前的