Make the system as simple as possible...DIY for a novice like myself, and with a minimal budget.
There are two ways to use a kite to harness wind energy.
Use a kite to carry turbines and generators up high and transmit the energy back electrically.
Use a kite as a wing and harness the power transmitted mechanically to the machine that it's attached to.
The latter has the advantages of: the kite flying around is commonly available (kite surfing kites), and the fewer things flying, the simpler.
Within this approach, we need to decide what kind of work the force of the kite lines is going to perform. Numerous approaches have been or are still being pursued by from a "laddermill", to a carousel, to other notions.
Trying to keep things as simple as possible, we emulate the well-proven interaction of kite surfers with large kites. One way to do this is to have the lines wind and unwind a spool.
We take the approach of dividing the system into two subsystems.
I've designed and built a drive/recoil system that assumes that that kite is attached via a single line around a single spool.
We want to hook the drive/recoil system up to a kite. We can do it via the single line seen in the video attached to something, or we can replace the single line with multiple lines. We're still figuring it out.