The Sharada script was used primarily for writing Sanskrit. In order
to represent Kashmiri, three additional signs were added to the script.
A below-base slash that resembles the Devanagari virāma:

An above-base bar that represents the Devanagari anudatta:

An underdot that is similar to the Devanagari nukta:

I am currently researching these signs. Please contact me if you have
information about the use of these signs for writing Kashmiri.