Thanks for that Lynne, I tried using global_start which I thought would precede everything else but no luck. However (as Seven Skins has said in the thread you mentioned) I too can output values directly from the plug-in, but I can't seem to insert a template.
So where as this works:
Hook: global_start
PHP Code:
$simpleWord = "word";
vB_Template::preRegister('header',array('show_simpleWord' => $simpleWord));
This doesn't:
Hook: global_start
PHP Code:
$templater = vB_Template::create('tmplt_simpleWord');
$templateValues['show_simpleWord'] = $templater->render();
vB_Template::preRegister('header', $templateValues);
Please consider this thread closed as I will be following Seven Skins'
thread for a solution instead.