After opening attached tcw file, scroll up and scroll down doesn't work. You can encounter a similar problem if the camera settings of your file are same as the attached sample file.
The reason for this behavior is the wrong camera parameters (position and target point) . The camera is too far (unreal) from the subject. To fix the problem, we need to move the camera closer to the object.
Work around:
2) Copy the drawing and paste it on to a new file and then scroll up and down.