Thanks for the thorough debugging here, @Garrett_Giles and @PascalX. You’re right that Composer 2 and Auto mode were experiencing issues, particularly on April 11. Manually selecting a specific model is the correct workaround for now.
The team is tracking this and working on improving Composer 2 and Auto mode reliability. If anyone here is still experiencing hangs after switching to a manually selected model, please share a Request ID, and we can check the backend.