We put together a USBizi updater application. It will erase the device then update the firmware from the SDK.
So when the firmware needs to be updated, just run this application. No need for Tera Term.
Hopefully this will make things easier.
The USBiziUpdater.exe is now part of the GHI NETMF and .NET Gadgeteer package. Which is #3 under system preparation.
Edit: This is now part of the SDK.