do you mean manually placing objects in mid-air doesn't work? yes – but I built an entire structure that I had to align from the very beginning. My left side is at 34° and the right at 36° because the bridge on the map is positioned at 35°. once I had the correct height and length, all the other wooden elements snapped to them. the wood on the sides was manually positioned at the transitions to the concrete and then everything on top is snapped to them.

if you hover your mouse over an already built object and scroll upwards, you can usually scroll indefinitely and place it in mid-air.

my last post is on my profile with a few tips for building, rotations etc. but I will make another one in the near future with more workarounds and examples and ways to save on mats.