Variable passed to BarChart by OokTech not working

Hello all,

I’m trying to use the Bar Chart plugin from OokTech found here BarChart Demo Edition — a demo of the plugin
with a variable. Below is my code. I’ve tried all of the different ways of passing a variable that I know of (<variable>, $(varaible)$, etc. But none have worked. I’ve even tried using the transclude widget, but that doesn’t seem to run the ProgressBar plugin at all. I know I’m missing something, but have no idea what it might be. By the way, if I just put a number instead of the variable ([550] instead of ), then it works just fine. Help, please!

<fieldset class="rw-fieldset-right-gap">
  <legend class="rw-legend"># of AM Stations by Frequency (10 kHz spacing)</legend>
  <table class="dx-table bct">
    <tr>
      <th>Freq<br>(kHz)</th>
      <th>Count</th>
      <th>Bar</th>
      <th>Stations</th>
    </tr>
    <$list filter="[tag[DXLog]field:dx-class[MWBC]get[dx-freq-khz]unique[]nsort[]]" variable="freq">
      <tr>
        <td><$text text=<<freq>>/></td>
        <td><$count filter="[tag[DXLog]dx-class[MWBC]dx-freq-khz<freq>get[dx-station]unique[]]"/></td>
        <td style="width: 10%;">
          <$ProgressBar
            filters="[tag[DXLog]dx-class[MWBC]dx-freq-khz<freq>get[dx-station]unique[]],[title[Bar Chart Max]get[text]split[ ]]"
            colors="#5B6F55,#f1ebda"
            class=""
            height="0.6"
            height-unit="em"
            label=""
          />
        </td>
        <td>
          <$list filter="[tag[DXLog]field:dx-class[MWBC]field:dx-freq-khz<freq>sort[dx-station]get[dx-station]unique[]]" variable="station">
            <$link to=<<station>> />&nbsp;&nbsp;
          </$list>
        </td>
      </tr>
    </$list>
  </table>
</fieldset>