This is my interpretation of Roland's travels through Mid-World. Or through the first, second, and third book. Everything in my opinion is correct, except for one thing.
King stated at the end of the Gunslinger/begining of the Drawing of the Three that Roland sat facing West watching the sun set on the Western Sea. That contradicts what he has said about all the other directions, because then Roland must have been travelling West in the first place. In the books Roland then headed north (along the beach) and southeast again (along the path of the beam). That would mean he would be going in a big circle if he came from the east in the first place and truely watched the sun set facing west.
That doesn't make sense, and it's a very real possibility that King made a mistake. But another explanation is that during the time Roland was 'asleep' with Walter everything 'moved on' and Roland actually did backtrack and turn back towards the way he came. I have trouble grasping that idea though.
Another weird point is that King said the Beam Portals borderd Mid-World. In my map it isn't on the border of Mid-World. I think it's smack dab in the middle of it. But then again, how big is Mid-World? My scaling is wayyy off!