Can you show us a image of how you have setup your Value List at the moment?
If it is just based on that first field, FileMaker automatically sort them in ascending order. Only way for you to get them in other order is to create a table with your different values and have a Sort Order field (that is unique number) and your Field. Then base your Value List show only value from first field. This will give you the sorting that you ask for. Then you use Menu Value List on your field store that Sort Order field and show another field that is related