on the product detail page, change line 429:
$query_OptionValues = sprintf("SELECT options.OptionName, productoptions.ProductID, products.ProductLive FROM options INNER JOIN productoptions ON productoptions.OptionID = options.OptionID INNER JOIN products ON products.ProductID = productoptions.ProductID WHERE OptionGroupID = ".$row_ProductOptions['OptionGroupID']." AND GroupingID = (SELECT GroupingID FROM productoptions WHERE productoptions.ProductID = ".$PIDParam_ProductOptions." LIMIT 1) ".$AddToWhere." ORDER BY OptionName", GetSQLValueString($OGIDParam_OptionValues, "int"));
to:
$query_OptionValues = sprintf("SELECT options.OptionName, productoptions.ProductID, products.ProductLive FROM options INNER JOIN productoptions ON productoptions.OptionID = options.OptionID INNER JOIN products ON products.ProductID = productoptions.ProductID WHERE OptionGroupID = ".$row_ProductOptions['OptionGroupID']." AND GroupingID = (SELECT GroupingID FROM productoptions WHERE productoptions.ProductID = ".$PIDParam_ProductOptions." LIMIT 1) ".$AddToWhere." ORDER BY OptionID", GetSQLValueString($OGIDParam_OptionValues, "int"));
this will set the list to display in the order you add the options.