Hi:
Yes, if you look at how the "settings" work (ABCD...). It is possible to write similar "human readable" files. Not text files but xml files where you can have different gains for different volumes. Also, if you don't want to control the SigmaStudio schematic directly you can use the sequencer window to just write to those memory locations that contain the volume parameters for multiple volume, all at once.
Hope this helps.
Miguel