I'm still learning and I am currently having problems positioning unconnected bones accurately in pose mode when using the 3d cursor.
I have one bone positioned correctly and I then need to add a new unconnected bone so I select bone 1 in edit mode and then press Shift+A to add a new bone. I then need to align it to a object so I switch to pose mode and then select the object and press shift+S and select cursor to selected, then I select the bone and press shift+S and select selection to cursor. The bone is now positioned correctly but if I switch to edit mode then the bone is in the wrong position. Am I doing something wrong?
All your bones need to be positioned correctly in Edit mode. In Edit mode you will build the basic/rest pose of the character. All the changes you will make in Pose mode are only for animations purpose (or to create static particular poses) and won't affect the bone positions in Edit mode. So if the bone aligned to an object is supposed to be the rest pose, you have to do it in Edit mode, if this is supposed to be an animation pose, do it in Pose mode.