One of the things about maintaining a Ubiquiti network at home is that you need a dedicated controller. I've been using a Mac to do this, but when you reimage you have readopt everything.
Instead, there is another option, use a small \$70 dedicated computer that acts as a controller. It connects to the Unifi cloud and essentially allows cloud access.
After you get the thing, you need to plug it into a Power on Ethernet port (or if you don't have one find a micro-USB cable and power it that way). Make sure you stick the SD card that is included in it. You will know that it is powered on, when the white light at the top turns on. They supply this tiny and stiff Ethernet cable, but I found putting a regular cable in allows the key to rest on top of your router.
Then you need to use Chrome to login to your unifi.ubnt.com cloud site. This has your configuration information and you have previous set this up to talk with the dedicated controller. When you do this turn on Cloud Key discovery to on and it will ask to download a Chrome application.
After this is done, you should see the Unifi controller. Most likely you will have to update the firmware, you do this by following the directions on you unifi.ubnt.com site which helps you to navigate to the IP address of the and then gives you default login of root and password of ubnt. When you logon, it will ask for a new password. Make sure to save it in 1Password.
Then go to the maintenance tab and click on Check for new Firmware to make sure to get the latest. It will take a while for the Cloud Key to reboot.

## If you are building a new network

After this is done, return to the unifi.ubnt.com page and do a Discover Cloud Key on again, you will see a Unifi Cloud Key entry, click on the Adopt button at the far right this will jump you to the Manage Wizard page on the Cloud Key.

## If you are migrating from an existing controller

Note that since have already configured the Unifi APs, then you will not see anything in the Configure devices tab, you will have to adopt them later.
The default wizard assumes you are just starting all over again, but you can use an existing backup file to get all the setup information if you are on your current computer with the Unifi Controller running. So what you want to do instead is start that computer up, The steps are to make sure to upgrade the controller software to a version number that is as high as the Cloud Key.
Then you want to export the site backup file from the current controller to the new Cloud Key. Then you will have a duplicate configuration, shutdown your existing controller and the Cloud Key should take over. Heck what could go wrong 🙂