How do I give our external auditor access to the audit?

Open the run, then the header gear → Access (the Auditors tab): invite the audit firm's people by email. They get the Auditor seat, which reads only the runs they have been granted — the working papers, versions, workbook and evidence — and asks or comments on queries; it does not edit a paper, sees no live ledger rows and never sees the close-out list. Each grant has an expiry. Until someone is invited the tab says 'Nobody from the audit firm has access yet'.