I am not a professional and don’t know if this is normal.
You are in good company, namely
from a “non-expert” person
who apparently
misplaced it.
that in some places it looks “untidy” and some corners look a bit worn off.
More worn than by ten years of pub visitors, I would say. In the past people said "Foolish hands smear table and walls" – apparently they have now extended their area of activity to floors as well. I have never seen brand-name goods like this. I have no talent for such things and yet I imagine I would have done it more beautifully even in dim light.
everywhere little stones, sand, dirt and thousands of scratches. I am struggling to stay cool. Despite two warnings to the developer, the parquet was not covered.
Even English dirt in Romania causes scratches, it’s known beyond all language barriers that only covering would have helped there. But well, that must now be completely removed, then the scratches don’t matter.
The developer is firmly convinced that it’s fine as it looks now and exactly matches the manufacturer’s picture hahah
He should sign that someone at his expense will restore it to exactly this condition. By "developer" you probably mean a construction
contractor, otherwise you wouldn’t be anywhere near there yet (?). Clear case: refuse acceptance.