Well according to the interview they have been developing this game for two years this April, so it looks more like this was their "big" project and they used the adventure games as side-projects to keep them going. Or that's my speculation.
I don't know. Their primary focus was always adventure games. This RPG project is their first, as far as I know. I see it this way: they started this project few years back to "try something new", but didn't really have enough money to do it seriously.
Big success of their newest games gave them money to devote into many projects at once. Even now, they are creating at least 3 different adventure games and this RPG.
It's pretty impressive, especially when it's almost certain that their adventure games will be top notch. Especially that "rabbit" one looks promising.