Regarding this one, what block was the villager laying? They hold whatever the next construction block is, and there are edge cases which don't display properly. It would be very helpful to know what was the block in question.
Thanks, that explains things, it's due to Millénaire still using the old "wooden slab" that's actually a retextured stone slab in some older buildings. I'll switch the buildings to use the new one and that should solve this as well.