Hiding a .tpl from the user when they preview?

System

Given the following data-type in templating.cfg:

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<data-type name="builder" dcr-type="iwov">
  <presentation>

    <template name="builder.tpl" extension="asp">
      <locations>
        <branch vpath-regex=".*" preview-dir="/">
          <directory dir-regex=".*" />
        </branch>
      </locations>
    </template>

    <template name="index.tpl" extension="asp">
      <locations>
        <branch vpath-regex=".*" preview-dir="/">
          <directory dir-regex=".*" />
        </branch>
      </locations>
    </template>

  </presentation>
</data-type>
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I would like to hide the index.tpl presentation template from the user so that it does not give him a choice when clicking on "Preview". If I remove index.tpl from templating.cfg, then iwgen (later in the workflow) fails, complaining that it "does not have a configured filename extension". I tried using an "<allowed>" section, but it appears only to work at the <presentation> level, not at the <template> level.

Does anyone have any thoughts?

Thanks in advance,

Dan Pike
Portland General Electric