Looked at in the running app: without a configured mirror the dialog
offered Download / Try Again that could only fail; it now shows the
manual-install hint and Close (an agent confirming still gets the
reason). "A one-time download of about 3.4 GB, saved in <folder>"; a
cancelled download is reported as stopped (resumable), not failed.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>