The Text Instrument is a text box that staff can use to enter anecdotal data (e.g. ABC data, general notes, etc). This instrument is generally used in addition to other data collection instruments. The data collection interface looks like this:
If you elect to have the done button present, it will require the BT to enter something into the text box. If you deselect the presence of the "done" button, then the BT can skip the text box feature when it is not relevant.