Yup, within CB > Plugin Management edit the Default template then under Layout > Registration you can specify a Header and/or Footer for additional instruction.
My client feels that the hover-over instruction on each field is missed by people filling out forms.
Those don't have to be hover based. Edit your fields in CB > Field Management then under Parameters > Layout set "Icons Display" to a text display. For example "Only Info Text" will just render the description as text instead of an icon. Now set "Input Description" to "No" to remove the final hover description on the input itself. Alternatively you can use the layout parameters for each of our views to add additional instructions to any fields view.