By default the options are listed by the name of the option. This is controlled by the query on the product details page on line 429. In this query you can update this order by to be based on the id of the option, this will list the options in the order they were added to the db.
The end of line 429:
ORDER BY OptionName", GetSQLValueString($OGIDParam_OptionValues, "int"));
Update it to be like this:
ORDER BY options.OptionID", GetSQLValueString($OGIDParam_OptionValues, "int"));
Give this a try and let us know how it works for you.