This FAQ reflects changes included in MCBackup 18.104.22.168. Please update if you haven’t already!
MCBackup doesn’t recognize my Minecraft installation!
There are a few possibilities. The first one is that you have not played Minecraft yet, and a saves folder has not been created yet. The other possibility is that you have not configured MCBackup to use the launcher you are using: see How do I configure MCBackup to use the Technic Launcher/FeedTheBeast/ATLauncher? The last possibility is that there is a bug in MCBackup, and you should file a bug report if you think that is the case!
How do backup groups work?
Backup groups are a simple way of organizing your backups. You can add, remove, rename, and change the order of backups groups by clicking on the small edit button (pencil with a plus symbol) beside the group names in the main window, or by going to Tools > Preferences > Groups. To create a backup in a group, select the group in the Backup window by using the dropdown menu on the left of the Start button
How do I configure MCBackup to use the Technic Launcher/FeedTheBeast/ATLauncher?
Go to Tools > Preferences. In the Folders tab, under Installation Type, click the button with the name of the launcher on it. You will be prompted to select the base folder (the one where you installed the game). Once it is selected, you should be good to go!