You're right chuckkahn, the backup solution is not very good. But as DTlow mentioned, it really is just a precaution in case something goes horribly wrong. It isn't necessary for the move to the alternative version of Evernote.
To create the backup,
select all your notes using Cmd+A, you should see the count of selected notes displayed just above the buttons for merge, share, create table of contents, etc.
On the menu choose File>Export Notes...
enter the file name and location for the backup.
After it starts you should see the count of saved notes progressi