It likely would be easier seeing exactly how you've set up your project to help with your primary issue.
I'm guessing, through your depiction of "middle screen skipped" that you may have a serie of events that will happen in line.
Moving your camera from a position A to a position B, and in the next event checking if the camera is in B and moving it in C.
The issue is that events are read from top to bottom, so the first event is true, and so the camera is moved to B. Then the next event is checked, and is true, since it checks if the camera is in B, which it is since it has been moved in the previous event.
To correct, make sure to add a system condition "Else" in the second event.
That's the best I can guess without seeing exactly how you've made your project. Consider posting your capx this will make it easier to investigate the issue.
"Scroll to" action is reliable, unless you've modified the layer's parralax property which may appear as "different".