This function allows you to back up individual registry sub keys. It will export a registry file (.reg) to the backup folder.
These can be imported back into the registry from Regedit, the Restore Registry Entries menu or by right clicking the .reg file from the backup folder and selecting Merge.
If you wish to import the registry file into another Identity, for example, the Signatures subkey, use the Replace | {USER_ID} to change the {USER_ID} in the .reg file to the other Identity's {USER_ID} then import the new .reg file created in the backup folder by right clicking and select Merge. Be sure you have the correct {USER_ID} you wish to replace. You can copy the {USER_ID} you wish to change it to by clicking on the Select {USER_ID} dropdown list and highlight the {USER_ID) then copy it (CTRL C or right click on it and select Copy).