I had the same problem, took me a couple hours to figure it out…
solution:
1. you need to login the the database that wordpress uses
2. execute query: select * from wp_options where option_name=’xlanguage_options’
3. it’s here, you have two options
a) you can try to fix it
b) just delete the whole record if you don’t mind making all the settings again (once you de-activeate and activate the plugin, it will create it again)
I took option b because I am just setting up
