Riven: Myst 2 is an adventure game and not an RPG, so let's get that out of the way. Yes, you can make a 1st person point and click game with it, esp. if it's like RealMyst or Myst V which were full 3D. However, I think Riven was a panoramic 2D game which is a technique that fakes 3D. You have a series of nodes and at each node there will be a panoramic 2D image that will allow you to look in every direction. When you click on a hotspot, you'll be taken to the next node, and in modern games of this type, a video clip will play that is the transition from the current node to the new one.

Creating this type of game would be easy from a scripting point of view, however the one trouble area, at least for me, would be how to handle the panoramic image. There are programs that will convert a 2D render to a panoramic format but I'm not sure how the code would look to make this look right during runtime including making sure it moves with the mouse movement correctly. And, of course, creating the 3D levels from which you'll take your renders and video files will take lots of time.