Translating pages, only the last version remains
The problem is the 'synchronize translations' submodule of i18n was enabled.
I took the privilege of disabling it on your test site. 
I know multilanguage is a tricky part in D7 but you should start with the basics of multilanguage by enabling locale, content translation, Internationalization, block languages, multilingual content and string translation. Just to get a feeling of what you're doing.
Later on you can activate some other submodules of the i18n module but in my opinion it is never a good idea to activate all at once. Activating to many modules at once can result in losing control of your installation like you're having right now.