another problem might be that, since the former owner used winder/thicker screws,
thinner diameter screw shafts will now work -
the thread size is now tapped out for a larger screw ...
MAYBE if some of the turns/threads are filed down/ removed, on the areas
that the lens needs to have these bigger threads be not bind it / make it
seized-up .. that might work .. but i don't think thinner screws will actually hold
since the holes are bigger now than they were before ...

maybe find a machinist in denmark who might be able to take the screws out, put
a threaded shaft in the holes and re-tap it out to fit thinner screws, and the shafts would have slots in them
to allow the lens to rotate as it was designed to do ...
or maybe find a tapered screw that looks like a golf tee / threaded peg
so it holds onto the top of the lens, but is smooth just takes up space in the bottom .. .

it sounds like a fun project ( kind of )