It appears none of the 'open in REPL' buttons work for the TelerikTaskBoard component. Some don't load any code in the REPL, others error at runtime.
I was trying to figure out how you got the Add Card pane to overlay the task board instead of push, when using the default Add Card hooks. The default behavior appears to be the Add card pushes the taskboard content. The online AI bot said this wasn't exposed via a parameter, but your demos that run in the Demos it uses an overlay. And I didn't see how this was working, as we want the same behavior.
Also there's no option to add TaskBoard as a tag here in forum posts.