StringBuilder - add default property to use for array accessors

I wanted to extend StringBuilder with Chars property like :

StringBuilder = public class mapped to …
method get_Chars(aIndex: Int32): Char;
method set_Chars(aIndex: Int32;value: Char ): Char;

property Chars[aIndex: Int32]: Char read get_Chars write set_Chars; default;

to access chars directly like for String.
It works fine for COOPER, but fails with ECHOES giving error :
(E90) Cannot load public key ““RemObjectsSoftware”: Keyset does not exist (Exception from HRESULT: 0x80090016)”
and I’m don’t how to do set_Chars for NOUGAT. I’m using the latest beta.
Can you suggest the solution?

you wil need to register a custom/dummy key called “RemObjectsSoftware” in order to build Sugar (or disable the String Name attribute in AssemblyInfo.pas.

Works fine now.