Lots of things from movies that don't currently happen are possible. For example, in The Sorcerer's Apprentice, brooms danced. If you take a broom and tie a rope around one end and then climb a ladder holding the other end of the rope, you can shake the rope and make the broom dance.
Not even close. The fictional pod engines had "anti-gravity" capability, i.e., they could hover and do drastic maneuvers like a sudden change from flying forward to shooting straight up, or in any other direction. Comparing them to cruise missiles is like comparing the maneuverability of a house fly to a passenger jet.
"Obviously, major tweaks need to be made."
No, you can't tweak a cruise missile, which uses conventional propulsion (jet engine), to obtain anti-gravity capability. You'd start with something else from scratch, using principles that are unknown to mainstream science.
"How hard can it be though ?"
Well, maybe it's already been done and they're just not telling us about it. But from the perspective of mainstream science: wicked friggin' hard.
There are many ways to fly. Major tweaks refers to creating something else entirely different from a cruise missile. Don't challenge me like that or I will have to create a "Pod" and prove you wrong.