I love the idea of the plugin, though, it's post on my group's wall every single time i press 'preview post' button. Even if radio 'do not post' is selected. It's very annoying, so i had to disable it :(
+ as an idea, maybe it's better to add an option to show a pop-up window after post publishing, "do you want to repost this to vk?"
+ ability to set 'pop-up' as default behaviour (on settings page)
+ ability to set do not post as default behaviour (on settings page)