Good to see these pics Bart.
I think it works okay, it is just a very small wing, quite high aspect (and not a perfect "profile" of course).
And such a wing is really really difficult to learn hydrofoiling on - this is why most are recommended buying a beginner foil first, even if they know they are gonna race, as you will learn so much faster
You could ride your friends hydrofoil right away you wrote?
If you can ride every weekend it is just dandy - but once a month on such a difficult wing will lead you nowhere...
You should move the mast more forward than in the first pictures I rhink - as if so far back, it will be almost impossible to push the foil "up" foiling.
And even if you succeed - it will be way too difficult to keep it in control there when you need so much rear foot pressure.
If you really want to learn on this difficult one, you should move the mast/wing further forward, and then just keep at it.
You need more speed with yours than others, and you must know it requires some extremely fine muscle memory that your head can not control - thus time and time and time, and because the wing is so small and narrow, it requires a lot more time than on other foils.