Find the documentation here: https://templates.cloudonaut.io/en/stable/ecs/
To update the region map execute the following lines in your terminal:
$ regions=$(aws ec2 describe-regions --query "Regions[].RegionName" --output text)
$ for region in $regions; do ami=$(aws --region $region ec2 describe-images --filters "Name=name,Values=amzn2-ami-ecs-hvm-2.0.20190204-x86_64-ebs" --query "Images[0].ImageId" --output "text"); printf "'$region':\n ECSAMI: '$ami'\n"; done