You can hard-code your choice of a template by altering the code in index.php, in your root folder.
Look for the code that says (maybe around line 135):
PHP Code:
$cur_template = $cur_template = $mainframe->getTemplate();
and replace it with:
PHP Code:
$cur_template = "name_of_template";
Where "name_of_template" is the name of your template. Make sure you use the correct capitalization and spacing.
Hope this helps!!