Key Schedule Node - Nothing Happens

Hi Guys!

After hours of work, I will give up and ask help for the gods of dynamo! hehe
I’m trying to write a single letter in a field inside of Key schedule, I’m using the key schedule node (Archilab 2020.23.11).
I’ve followed all instructions of this site:
But don’t work for me, just nothing happens!. Can someone help me?
(Revit 2020.2 - Dynamo 2.3)