This paper describes additional aspects of a digital tool called the ‘Textual History Tool’. We describe its various salient features with special reference to those of its features that may help the philologist digitize commentaries and sub-commentaries on a text. This tool captures the historical evolution of a text through various temporal stages, and interrelated data culled from various types of related texts. We use the text of the Kāśikāvṛtti (KV) as a sample text, and with the help of philologists, we digitize the commentaries available to us. We digitize the Nyāsa (Ny), the Padamañjarī (Pm) and sub commentaries on the KV text known as the Tantrapradīpa (Tp), and the Makaranda (Mk). We divide each commentary and sub-commentary into functional units and describe the methodology and motivation behind the functional unit division. Our functional unit division helps generate more accurate phylogenetic trees for the text, based on distance methods using the data entered in the tool.