Consider the ship to be stationary and you aim the gravity field at a point in space and bring that space to the ship. The distance between the ship and that part of space is diminished because the gravity field curves it toward you.
Sure, I'll buy that.
"Empty space" shouldn't take all that much effort to compress after all as it's, well, "empty" after all.
Then when the space compressor is shut off the space behind the ship would unfold, seemingly giving you distance between ship and Earth.
It would be helpful if we could put together such a strictly theoretical working hypothesis for, which I'd like to refer to as, jumping through hyperspace, I.E in which order our ship would have to power all the, still unbuilt, circuits, builds, etc, from start to finish, for one complete such jump.
Like for instance start out with shielding the ship from the gravity generator, then home in on the final destination, then...........
Just a theoretical step by step list detailing what needs to be done.
Then brainstorm a bit and maybe add and/or remove things from this list.
What would you say Nav is needed and in what order, etc etc.
Never mind that nothing of this is invented, not just yet anyway
;-)