Guide, lead, steer, pilot, engineer are comparable when meaning to direct a person or thing in his or its course or to show the way which he or it should follow.
Guide usually implies assistance either by means of a person with intimate knowledge of the course or way and of all its difficulties and dangers or by means of something (as a light, the stars, a principle, or a device on a machine) which prevents a person or thing from getting off course or going astray.
Lead stresses the idea of going in advance to show the way and, often, to keep those that follow in order or under control. Often, especially in idiomatic phrases, lead implies the taking of the initiative, the giving of example, or the assumption of the role of leader, director, or guide.
Steer stresses the guidance by one able to control the mechanism which determines the course or direction (as of a boat, an automobile, an airplane); it carries a stronger implication of governing or maneuvering than any of the preceding terms.
Pilot implies the assistance of a person competent to steer a vessel safely through unknown or difficult waters (as into or out of a port). In its extended use it implies guidance over a course where one may easily lose one’s way because of its intricacy or may run afoul of various obstacles or dangers.
Engineer means to lay out and manage the construction of some project (as a tunnel under a river, a highway, or a bridge <a firm of experts was called upon to engineer the irrigation project> but in its more common extended sense it means to serve as a manager in carrying through something which requires contrivance and maneuvering.