I forked and cloned the repo, followed the very simple config instructions, thank you, and got it to work. (On the localhost)
Workflow connected without any issues.
However, after having just a couple of very short interactions back and forth with the workflow, the application becomes non-responsive.
There aren't a lot of messages in the history, barely filling the screen.
Prominent issues:

• Scroller (I can see it's in an iframe) bar reacts to the mouse, but the content is frozen for a long time, takes up to 5-10 seconds to react.
• Switching away and returning to the tab/browser window renders the entire application node white, with no content at all. Takes a randomly long time to go back to normal, sometimes even the rendered content is frozen as above.
• Tab memory use spikes up to 20GB.
• Tab with the app crashes into "not responding" state.

EDIT: Noticed similar issues in the https://chatkit.studio/playground
The preview in https://platform.openai.com/agent-builder/ works perfectly, though.

Windows 10, latest Chrome. Lots of RAM and CPU power.