When looking east and using flexibleBlockPlacementOffset and flexibleBlockPlacementRotaion and accurateBlockPlacementReverse the stair should be facing the opposite side from you but instead it ends up facing south.
It does work in the other sides (south, west, north).

when you do it this way:

it will end up like this:

but it should be like this:

This has been a known issue for a long time, and it has basically always been broken like this. The current code is such an unmaintainable mess, that I haven't even looked into trying to fix this yet. The entire placement related code is meant to get a total rewrite "soon"-ish during the mod code clean-ups.

This has been a known issue for a long time, and it has basically always been broken like this. The current code is such an unmaintainable mess, that I haven't even looked into trying to fix this yet. The entire placement related code is meant to get a total rewrite "soon"-ish during the mod code clean-ups.

Ok.