Hi, sorry about that I will see what I can do about documentation when I update it.
About the delegates.
First to create a Delegate what you need to do is in the Project tab(the tab with your files and folders) right click on a empty space then go to
Create > VisualScripting > Community > Code > Delegate now in the inspector you can chose the type for the delegate your want
then you can open the C# Preview which is in Windows > Community Addons > C# Preview then you can press compile this will create the delegate for you. if you don't see any code in the preview make sure to click on the Delegate asset once the window is opened.
And if its not compiling then Open the Utility Window and press compile all. which should be in Windows > Community Addons > Utility Window if not then right click on a empty spot in a graph and the option should appear there to open the Utility Window if i am not mistaken.
Now you can go to a graph and Add a Create Action or Create Func like in the screenshot depending on the type you chose in the inspector when creating the delegate. Click on the Node and in the Graph Inspector you can set the type of the action there.