I experience a similar issue. The app stays open a bit longer, so I can successfully log in, but it always crashes / closes during the first download (in my case, from Disney+). macOS 26.5.2. The log only has this at its end:
2026:07:03-18:25:08 0x325033000 [Info]: [default] === StartDownload() SUCCESS: Starting download with 1 periods ===
2026:07:03-18:25:09 0x317d09000 [Info]: [disney.auth.context] updateHeaderMap: intercepted headerMap updated, keys: 18
And there is no crash report, the app just closes silently.