Your adding a dependency on *Registry_key["HKLM\\System\\CurrentControlSet\\Services\\${name}"]*, but this resource is not defined, is  it?

I think you can avoid this dependency because requiring *Exec["create-python-${name}-windows-service"]* ensures you'll have that key in the registry. Otherwise, you should create *registry_key {"HKLM\\System\\CurrentControlSet\\Services\\${name}": ...bla....}*