A general overview of a manual migration is to backup the old hub, save locally and power off the hub. On the C-8, restore the file just created. When it boots, take a look at the Apps and disable those Apps that will collide with the exact same app on the old hub. Then you can power up the old hub and it will work the same as it did, the new hub is not competing with it.
I think it's easy to do Zigbee using the technique of Removing the Zigbee device from the old, which puts most Zigbee devices into pairing immediately.. then quickly running Zigbee include on the C-8. The device will drop right into place. Any that don't magically go into pairing, use the "Pairing Dance" per the manufacturer and again, it will pair and drop back into place.
ZWave is more steps but does not involve the old hub at all. Prep the C-8 by visiting each ZWave device info page and a) alter the name slightly... I add "old" to the end. b) alter the DNI slightly...I add "x" to the end. The purpose of this is to prevent collision on the DNI. In my case, I have 30 ZWave devices to migrate, so I look at Settings: Z-Wave Details and for each device in which the Node column value is less than 31 (decimal) I alter the DNI. In my case there were only 4 device that had a DNI less than 30, so the DNI alteration isn't a big deal.
Identify the ZWave device you want to migrate. On the C-8 alone, start a ZWave Exclude. Start the device "Join Dance" and verify that "unknown device is excluded" appears. This is an important step. It 1) confirms you're doing the "dance" correctly and 2) confirms the device is in range of the C-8. Repeat until you see the exclude message. Immediately click the ZWave Include button and repeat the "Dance" and the new device should join quickly. I advise you to select NoSecurity if offered. Give the device it's original name.
Go to Settings: Swap Apps Device and select the old device on the left, new device on the right, click "Swap old device in all apps" button. Go to the device info page for the OLD device verify there are no Used By and remove it.
Repeat til done.
