We provide license key of Visual Composer in download package, you can find it in obtheme-montanaVisual Composer (We bought extended license of this plugin) but current have note solution for activate with this plugin. license key only can activate 1 time 🙁
We created new ticket on http://support.wpbakery.com/ and here is the answer from developer of Visual Composer
It is not possible for theme buyer to activate the license (and hence to auto-update the Visual Composer) as they have not purchased the license directly from us, but has received it in-directly from the theme. In this case, you must update the version in the theme and must release a theme update which the buyers can download and hence in-turn will receive the latest version of Visual Composer.
We’re sorry about this inconvenience but we will update our themes to run follow Visual Composer updates.