Ok strange behavior time.
I am testing using MOULa export and the Destiny Shard.
Ladders are modeled and I am using the ladder tool.
My ladders have a lintel step at the top and all of the components are child linked to a parent empty that sits at the center of that lintel just to keep everything together.
After parenting I have to re-enable all plasma objects or the ladders just do not export (that is actually no big deal).
Ladder rungs are aligned with the boxes generated by the tool then those boxes and the floor level boxes are removed leaving only the upper and lower entry points.
This is just to reduce an already large number of objects.
All of this works fine till I child link the upper and lower entry boxes to the ladder empty.
At this point I get a couple of strange behaviors either I am unable to walk away from the bottom of a ladder spinning round and starting to re climb or when I get to the top I immediately spin round and then I can back up then turn I can sometimes get away with not descending.
At the moment I have a work around where I use the parenting for any duplication and rotation of ladders then break the parenting before doing the re-enable plasma and export.
As I say the work around works and this should be considered as a heads up on usage of the ladder tool, for most age builders ladders will be an infrequent use.
I am not expecting a fix just saying it is something to consider when using the ladder tool.