Failed to run aligner for XX01ZVNS2B upload_2

[tdudgeon]

This error occurs:

$ python -m xchemalign.aligner -d data/XX01ZVNS2B/work/upload_2
Using data/XX01ZVNS2B/work/aligner.log for log file
INFO: initialising logging at level 0 at 2024-05-23 16:21:33.421886
INFO: aligner:  Namespace(version_dir='data/XX01ZVNS2B/work/upload_2', metadata_file='meta_collator.yaml', assemblies=None, log_file=None, log_level=0, validate=False)
INFO: Running aligner...
INFO: Performing alignments
INFO: Updating from previous directory: data/XX01ZVNS2B/work/upload_1
Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "/data/github/im/fragalysis_api/xchem-align/src/xchemalign/aligner.py", line 852, in <module>
    main()
  File "/data/github/im/fragalysis_api/xchem-align/src/xchemalign/aligner.py", line 839, in main
    a.run()
  File "/data/github/im/fragalysis_api/xchem-align/src/xchemalign/aligner.py", line 231, in run
    new_meta = self._perform_alignments(input_meta)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/github/im/fragalysis_api/xchem-align/src/xchemalign/aligner.py", line 309, in _perform_alignments
    source_fs_model = dt.FSModel.from_dir(previous_output_path)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/github/im/fragalysis_api/xchem-align/venv/lib/python3.11/site-packages/ligand_neighbourhood_alignment/dt.py", line 169, in from_dir
    return FSModel.from_dict(dic)
           ^^^^^^^^^^^^^^^^^^^^^^
  File "/data/github/im/fragalysis_api/xchem-align/venv/lib/python3.11/site-packages/ligand_neighbourhood_alignment/dt.py", line 220, in from_dict
    alignments[dtag][chain][residue][version] = LigandNeighbourhoodOutput.from_dict(
                                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/data/github/im/fragalysis_api/xchem-align/venv/lib/python3.11/site-packages/ligand_neighbourhood_alignment/dt.py", line 39, in from_dict
    aligned_structures={k: Path(v) for k, v in dic["aligned_structures"].items()},
                                               ~~~^^^^^^^^^^^^^^^^^^^^^^
KeyError: 'aligned_structures'

The collator output looks sane to me and I can't see any obvious cause.

@ConorFWild can you have a look at this and see if you have any ideas what is wrong.
I have data that can be used to reproduce this, but it will be a large dataset.