The sha256sum checked out ok, but the live-session boot hangs with that error message. I let it go for 2min 30sec then powered off.
Reverted back to the other iso so it would boot, still sat for about 20 sec then completed.
On both boots, it hangs right after I get the message about Bluetooth patch not applying. I checked the dmesg output after a successful boot, and Bluetooth is followed by a bunch of networking messages for eth0 (the wired interface on this laptop). Is the dmesg output in order, so maybe a networking/dhcp issue?