Question Regarding Kutakshar Options

[amikigu]

Greetings. I greatly appreciate the work that has gone into this beautiful font and the tutorials. After installing the fonts and watching this tutorial:
https://www.facebook.com/watch/?v=1119822812425500 ...I was able to view Kutakshar font in Adobe Illustrator, but I was unable to use the Kutakshar Forms and Extended Kutakshar forms.

After installing the font and then opening Illustrator, I first used https://www.lexilogos.com/keyboard/sanskrit_devanagari.htm ...to create words in Devanagari, then copied the output text into a text box in Illustrator. With the text box selected, I then chose the "NithyaRanjanaDU-Regular" font from the font menu. With the text box still selected, I was able to use the OpenType button to select the "Alternate Characters" and "Alternate Top Matra Forms and Swasti" options, and the relevant characters changed in the text box. But for some reason, when I attempted to select the "Kutakshar Forms" and "Extended Kutakshar forms" options, nothing changed.

Should I be using a different way to bring in Devanagari text, or are there other Illustrator settings that would be relevant to making this font work at its fullest potential? Thanks in advance for any advice.