Hi Had the same issue:

Problem seemed to be,I copied exactly from the example template into a text file, where the text file formatting disappeared in VIM.

I added the "spaces" and "returns" then ran the following after getting the imageID from "nova image-list":

heat -d stack-create -f test-stack.yml -P "ImageID=f514eeae-9b49-499c-aaa4-911a66f30c61;NetID=$NET_ID" testStack

It then worked.

###################################################################################################

heat_template_version: 2014-10-16
description: A simple server.

parameters:
 ImageID:
  type: string
  description: Image use to boot a server
 NetID:
  type: string
  description: Network ID for the server

resources:
 server:
  type: OS::Nova::Server
  properties:
   image: { get_param: ImageID }
   flavor: m1.tiny
   networks:
   - network: { get_param: NetID }

outputs:
 private_ip:
  description: IP address of the server in the private network
  value: { get_attr: [ server, first_address ] }

Try running the command as below specifying the parameters as per your environment:

heat stack-create StackName -f filename.template -P "image=<ImageName/ID>;public_network=<UUID/Name>;private_network=<UUID/Name>;key=<SSH_key_name>;flavor=<type>;database_name=<db_name>;database_user=<db_user>;database_flavor=<db_flavor>;database_password=<dbPassword>;database_root_password=<db_rootPassword>"

Also ensure there exists all these parameters properly specified with correct indentation in your template(YAML script).

BTW, you can use the names instead of UUIDs for those "image" and "networks: -network" properties, which would save you couple of nova outputs parses.