One thing I've found, when you are placing a single fitting with the slope on, the end facing away from you will slope down (as you can see with the green node) and when you rotate it to put the end toward you, it will slope up (blue node). A little hard to explain so take a look at the pictures. Just go to a 3d view and check which way the node is saying that the fitting will slope, and if that's not right, rotate the view to the look at the other side of the pipe.
This works for cutting a fitting in on a vertical run too.