I run Leap 15.1 on my desktop. I use eekboard software to type in Hindi and
Marathi languages using the "Inscript" keyboard layout. I could not find the
eleventh consonant that is "���" in Devnagri script on the keyboard. It should
have appeared at the spot the single quotation mark is put on the onscreen
keyboard (same as in US keyboard layout).

The same "Inscript" is used even in Windows (I may say universally) and this
consonant is there. The official site for "Inscript" also is fine. The problem,
I presume, is in the file used by eekboard.