Fields in Kibana 5 are non-searchable and non-aggregatable

Do you mean that Elasticsearch is running on your linux server, and that you are pointing the topbeat instance on your windows machine to it?

Are you using Logstash to index the data from topbeat, or did you configure it to dump directly into Elasticsearch?

If you are dumping directly into elasticsearch, I don't think that you need to manually load the index template.