Hi Aleksey,
I apologize for the lack of documentation here. We're working on a 3.0 release of Rogue that will not depend on Lift. We're using it in production at Foursquare now, just waiting for a few features to stabilize (and documentation to be written) before we release it. Most of our development has been on that branch, but we've been backporting features to the 2.x branch pretty regularly. The README there should be up to date.
Rogue should be compatible with lift 2.6-M4. I've only tried it locally with Rogue test suite and not in production, so I can't fully vouch for it. But we do use Lift 2.5.1 with the 2.11 version of the mongo java driver in production, so those should be compatible. I know there are some significant changes in the 2.12 version of the mongo java driver that are not compatible with Rogue.
Hope this helps. Let me know if you have any more questions!
Regards,
Jason