Prev/Next on field group horizontal tabs
OK, well before this is closed, I will post what I did in the hope it might help someone.

I added a #tab_back/#tab_next buttons to the form, and used a bit of jquery to handle the UI.

  var current_tab = 0;
  jQuery("#tab_back").hide();
  jQuery(".entitytype-tab_tool-form").find('input[type=submit]').hide();

  function click_tab(inc)  {

    newtab = current_tab + inc;
    if (newtab &gt;= 0 &amp;&amp; newtab &lt;= 4 )  {
      jQuery('.horizontal-tab-button-'+newtab).find("a").click();
      current_tab = newtab;
      jQuery("html, body").animate({ scrollTop: 0 }, "slow");
    }
    return false;
  }

  jQuery("#tab_back").click(function () {
    click_tab(-1);
    return false;
  });

  jQuery("#tab_next").click(function () {
    click_tab(1);
    return false;
  });

  jQuery('.horizontal-tab-button-0').find("a").click(function () {
    current_tab = 0;
    jQuery("#tab_back").hide();
    jQuery("#tab_next").show();
    jQuery(".entitytype-tab_tool-form").find('input[type=submit]').hide();
  });

  jQuery('.horizontal-tab-button-1').find("a").click(function () {
    current_tab = 1;
    jQuery("#tab_back").show();
    jQuery("#tab_next").show();
    jQuery(".entitytype-tab_tool-form").find('input[type=submit]').hide();
  });

  jQuery('.horizontal-tab-button-2').find("a").click(function () {
    current_tab = 2;
    jQuery("#tab_back").show();
    jQuery("#tab_next").show();
    jQuery(".entitytype-tab_tool-form").find('input[type=submit]').hide();
  });

  jQuery('.horizontal-tab-button-3').find("a").click(function () {
    current_tab = 3;
    jQuery("#tab_back").show();
    jQuery("#tab_next").show();
    jQuery(".entitytype-tab_tool-form").find('input[type=submit]').hide();
  });

  jQuery('.horizontal-tab-button-4').find("a").click(function () {
    current_tab = 4;
    jQuery("#tab_back").show();
    jQuery("#tab_next").hide();
    jQuery(".entitytype-tab_tool-form").find('input[type=submit]').show();
  });


For what it's worth, I didn't really need tutoring, just help knowing which avenue to explore as it could have been done many different ways.  Anyway, hope this helps someone.  feel free to pick at my javascript... It's not my forte.