Yes, I did play with that. And I also discovered that you really CAN get at that enclosing Div tag (around every element). It is "container_attributes", and is used as:

elements:
  - type: Text
    label: Client Name
    attributes:
       name: cname
       class: txtinput
       size: 55
       maxlen: 80
       value: %% client.name %%
    container_attributes:
       title: Name of Client
       class: txtContain
[download]

This puts my own class, "txtContain", in front of the "text label" classes already inserted by FormFu.