While the offered solution of changing the css will solve this issue for this one request, having had an opportunity to get to a computer the following is suggested to provide what looks like a more robust solution. So in following with the discussion of others that there should be no code changes needed to make whatever lowest, non-zero tab group be the default selected option (controlling the sort order by the admin settings), the template should do more to force the first tab to be the selected tab when the page is loaded. So in part I disagree that there is no "bug" with this template (even if the html validation issues previously referenced haven't yet affected the javascript/jquery).
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I *did* partially misunderstand one detail of the issue, thinking that selection of anything other than the new tab didn't work. ‎Instead the issue was that assigning a tab other than the new tab to be the default (first) tab did not force display of the associated content when the page was initially displayed.
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To resolve that issue regardless of the desired first tab (again as set in the admin), when the page loads, the javascript (or variation of) associated with showing the active tab and hiding the other tabs should be executed on the numerically (sorted order pretty much) first tab if one is displayed. The tabs are already presented in a sorted order based on the admin settings, so the issue is then to activate the first one.
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One way to accomplish this with regards to the above (even though one of the divs was commented out in the above provided code) is to add an on_load file such as:

includes/modules/pages/index/on_load_tabs.js
(or as necessary the name modified to be other than "tabs" such that it loads in the necessary sequence to support execution of the click operation)

Code:
if ($("#moduleMenu-wrapper").length){
  if ($("#moduleMenu-wrapper span").length) {

    var classList = $("#moduleMenu-wrapper span").first().attr("class").split(/[ \n\r\t\f]+/); //Get the class from the first span of the moduleMenu-wrapper and split it into an array such that can evaluate each element

    if (classList.length) { // If there is at least one element
      if ($("a").hasClass(classList[0])) { // If the "a" tag element has the class of the first element of the span (ie. navOne, navTwo, navThree, etc...)
        $(document).ready(function() { // Take action within this function
          $("a." + classList[0]).trigger("click"); // Activate the click of the "a" tag element having the above identified class
        });
      }
    }
  }
}