Tool Settings Explanation

Paste at original position: Pastes the duplication at the position it was copied.
Paste with constraints: Check to paste with constraints, uncheck to paste without constraints.
Paste with parenting: Check to paste with parenting, uncheck to paste without parenting.
Unfreeze all after paste: Check to unfreeze all entities after pasting.
Preserve frozen state after paste: Check to paste entities with their frozen state when they were copied.
Area copy constrained props outside of box: Copies entities outside of the area copy box that are constrained to entities inside the box.
Percent of ghost to create: Changes how many ghosts to spawn for the duplication, 100% = spawn all, 50% = spawn half, etc...
Area Copy Size: Size of the area copy box.

Offsets

Height Offset: Changes the Z height offset of the duplication.
Use World Angles: Modifys the angles based on the world's angles instead of the entity's.
Pitch Offset: Changes the pitch angle offset of the duplication.
Yaw Offset: Changes the Yaw angle offset of the duplication.
Roll Offset: Changes the Roll angle offset of the duplication.

Spawn Delay: The delay of how fast the contraption spawner can be spawned.
Undo Delay: The delay to automatically undo the spawned contraptions from the time they were each spawned.
Disable gravity for all spawned props: Spawns contraptions without gravity.
Disable drag for all spawned props: Spawns contraptions without drag.
Add spawner's velocity to contraption: Spawns contraptions with added velocity from the contraption spawner.

Copy Contraption Only: Will not copy an area, only the prop that is clicked and everything constrained to it.(So if the prop moves across the map it will still be saved.)
Overwrite File: Will overwrite the file name each time instead of creating a new file and appending a number.
Browse: Browse to the directory from the file browser and choose where to save the auto save and what to name it.