Hello Kevin,
I hooked up an external USB 3.0 WD hard drive and found that this wasn't supported by SeaBIOS as this used 4K blocks.
Do you have plans to support this in the future in some way? Or will this simply be incompatible without plans for support. (This isn't a problem but it's good to know what the plans are).
I haven't seen any devices like that - I was under the impression the 4K drives emulated 512 byte blocks. It should be possible to support them though. Can you send an email to the mailing list (and include a debug log)?
BR, Wim