when working with options that effect price, the key's are:
do not set the option in the add to cart button to make the option column update able from a select list, leve that option unchecked and create the select list for the option manually rather than having eCart create.
You need to create a lookup recordset that will filter the options column to lookup the option name and the option price.
In the add to cart behavior, bind the option column to the option name from the recordset.