The plugin avoids reimporting the scene or regenerating the materials automatically when the 3d file is loaded to respect any changes that the user might have applied manually to the Anima assets that are present in that scene. There are a few things that can be done after a scene is imported that only depend on the plugin side, like removing an actor that might not be wanted on camera, linking props to the Rigged actors, adjusting the materials generated automatically, or animating the scene helpers (for moving spaces like trains or elevators).
All those actions are lost every time the import process happens (or an Alive sync). Therefore, by not always re-importing the scene on the load process, we are allowing all those features to keep working. However, keep in mind they will work as long as they are done as the last step of the workflow, when there is confidence that the source anima scene will not change anymore.
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