A template is a saved search document that is always available from both the "Templates" menu and the HoudahSpot global menu item.
For a saved query document to be considered a template it needs to be saved to a special location. That location is ~/Library/Application Support/HoudahSpot/Templates. The tilde (~) character represents your home directory. When saving a HoudahSpot file you will be offered the opportunity to save to the templates folder.
Like all HoudahSpot query documents, saved templates retain the running state of the query. That is, a query that was live as it got saved will be live again when opened. (A query is live from the time the "Start" button is clicked until the "Stop" button is clicked.)
Thus we may distinguish two different uses for templates: live and ready templates.
Live Templates
These are queries that were saved while they were live.They are similar in purpose to the Finder's smart folders.
When you select this kind of template from the Templates menu, you see a results pane, and the query immediately runs.
By default, HoudahSpot comes with two such templates: "Applications" & "Recent Documents".
Ready Templates
These are queries that were stopped before they were saved as templates. You use these as starting points to formulate more detailed queries.
When you select this kind of template from the Templates menu, you see a query pane that you can modify as you like.
The HoudahSpot distribution includes one such template: "Long Lost Files". It is set up to look for documents modified some 10 years ago. You will probably want to adjust this each time you use the template.
You may open additional copies of an already opened template by holding the option key while choosing the template from the Templates menu.