Ive been playing this for years now. I just read all the complaints about unfair dice. Im not sure if its true, and Im not sure if I would have noticed anyway. The AI usually beats me, but I hadnt suspected cheating. Im used to playing GnuBG on my computer, which is also a very good opponent, but the two have different styles of play.
I usually play a match to 7 on expert level with tutorial mode on.
As for the interface, its very natural. There is no sound, but there is no wasted time with excess animation - its all about gameplay. I would like to see an "autoplay forced moves" feature for when you dont have the cube and are stuck on the bar. The autopilot feature sort of does this, but you have to turn it off manually.
As for the logic, there seem to be some problems with the AIs doubling logic. It often tells me that doubling is a bad idea when Im losing a post-Crawford game, with no hope of getting a triple game. Other than that, it seems reasonable most of the time. One big annoyance is that the AI NEVER resigns (at least in match mode). It will decline a double, but if it has the cube, this just wastes time when its obviously going to lose.