What do you mean by it is a list? Where is the list stored, within the customized field itself or did you create a custom module to manage a list?  What seems to be exported based on your description are the keys to the lookup.

If it is a custom module, you can’t export the data stored in the database which is used for the lookup is my thinking.

Thanks for the reply Phil.  I set the field up as “Drop down values” as that was the only way I could see getting a multiple choice response without the risk of user misspelling.  

What I want exported is the data in the field which has been completed.  I have worked out that the export shows the line number of which has been selected.  So I wonder if I made the key the data too, would that fix the issue for me?

So, to confirm you have a drop down list defined as a customized field in say the service order module.  The agent makes a selection and this selection is saved with the order (thus in the database).

Now when you try to EXPORT the service order, the data exported does not contain the value linked to the key of the drop down list but only the key itself.

What you suggest would give you your data in the export if the string value for the ID is not exported.  I might use a short code instead of the whole string just so you can recognize it but still keep the output reasonable sane.

Or you could create a module to manage the list itself and then define the custom field as a computed column looking up from the custom table containing the list.  That value would then be saved to the database and exported is how I think.