Hmm, chastised for using a version that was barely a day out of date, then release another 20 minutes after :(
For the record, v0.80 failed, while v0.81 succeeds. Used one click setup.
I spent most of yesterday trying to downgrade to 2.1 on my Old3DS. The downgrade installs without error but when validating the downgrade I find the same 8 mismatches every time. I have tried many times over, even replaced the update files on the SD card. I tried checking for false positives...