If the file were embedded, export field contents can export and open a copy of the file. You can set up the container field as a button to click using button setup or add a button next to it to do the same thing.
It's also possible to set up a calculation field with container as the result type that modifies the stored file path to a form that works for which ever OS platform is in use by the current user. This calculation field can then be double clicked to open the file.
For more on $path variables, container fields, and the scripts that can use them, see: Exploring the use of a $Path Variable in Scripts