diff --git a/molecularnodes/assets/MN_data_file.blend b/molecularnodes/assets/MN_data_file.blend
index 00583a75..3b80f9b0 100644
Binary files a/molecularnodes/assets/MN_data_file.blend and b/molecularnodes/assets/MN_data_file.blend differ
diff --git a/molecularnodes/io/cellpack.py b/molecularnodes/io/cellpack.py
index 28e794a8..ce90779e 100644
--- a/molecularnodes/io/cellpack.py
+++ b/molecularnodes/io/cellpack.py
@@ -59,7 +59,7 @@ def parse(file, name="NewModel", get_transforms=True, instance_nodes=True):
     
     chain_names = np.unique(mol.chain_id)
     
-    obj_data['chain_id'] = chain_names
+    obj_data['chain_id_unique'] = chain_names
 
     coll_cellpack = coll.cellpack(f"{name}")
 
diff --git a/tests/snapshots/test_cellpack/test_load_cellpack/bcif/chain_id_unique.txt b/tests/snapshots/test_cellpack/test_load_cellpack/bcif/chain_id_unique.txt
new file mode 100644
index 00000000..d5221b51
--- /dev/null
+++ b/tests/snapshots/test_cellpack/test_load_cellpack/bcif/chain_id_unique.txt
@@ -0,0 +1 @@
+['Cv0', 'Cv1', 'Cv10', 'Cv11', 'Cv12', 'Cv13', 'Cv2', 'Cv3', 'Cv4', 'Cv5', 'Cv6', 'Cv7', 'Cv8', 'Cv9', 'Ed0', 'Ed1', 'Ed2', 'Ed3', 'Ed4', 'Ed5', 'Ed6', 'Ed7', 'Ed8', 'Gb0', 'Gb1', 'Gb2', 'Gb3', 'Gg01', 'Gg02', 'Gg03', 'Gg04', 'Gg11', 'Gg12', 'Gg13', 'Gg14', 'Gh01', 'Gh02', 'Gh03', 'Gh04', 'Gi01', 'Gi02', 'Gi03', 'Gi04']
\ No newline at end of file
diff --git a/tests/snapshots/test_cellpack/test_load_cellpack/bcif/instance_names.txt b/tests/snapshots/test_cellpack/test_load_cellpack/bcif/instance_names.txt
index 6fc188ce..9b85243b 100644
--- a/tests/snapshots/test_cellpack/test_load_cellpack/bcif/instance_names.txt
+++ b/tests/snapshots/test_cellpack/test_load_cellpack/bcif/instance_names.txt
@@ -1,43 +1,43 @@
-0000_Cv0.002
-0001_Cv1.002
-0002_Cv10.002
-0003_Cv11.002
-0004_Cv12.002
-0005_Cv13.002
-0006_Cv2.002
-0007_Cv3.002
-0008_Cv4.002
-0009_Cv5.002
-0010_Cv6.002
-0011_Cv7.002
-0012_Cv8.002
-0013_Cv9.002
-0014_Ed0.002
-0015_Ed1.002
-0016_Ed2.002
-0017_Ed3.002
-0018_Ed4.002
-0019_Ed5.002
-0020_Ed6.002
-0021_Ed7.002
-0022_Ed8.002
-0023_Gb0.002
-0024_Gb1.002
-0025_Gb2.002
-0026_Gb3.002
-0027_Gg01.002
-0028_Gg02.002
-0029_Gg03.002
-0030_Gg04.002
-0031_Gg11.002
-0032_Gg12.002
-0033_Gg13.002
-0034_Gg14.002
-0035_Gh01.002
-0036_Gh02.002
-0037_Gh03.002
-0038_Gh04.002
-0039_Gi01.002
-0040_Gi02.002
-0041_Gi03.002
-0042_Gi04.002
\ No newline at end of file
+0000_Cv0
+0001_Cv1
+0002_Cv10
+0003_Cv11
+0004_Cv12
+0005_Cv13
+0006_Cv2
+0007_Cv3
+0008_Cv4
+0009_Cv5
+0010_Cv6
+0011_Cv7
+0012_Cv8
+0013_Cv9
+0014_Ed0
+0015_Ed1
+0016_Ed2
+0017_Ed3
+0018_Ed4
+0019_Ed5
+0020_Ed6
+0021_Ed7
+0022_Ed8
+0023_Gb0
+0024_Gb1
+0025_Gb2
+0026_Gb3
+0027_Gg01
+0028_Gg02
+0029_Gg03
+0030_Gg04
+0031_Gg11
+0032_Gg12
+0033_Gg13
+0034_Gg14
+0035_Gh01
+0036_Gh02
+0037_Gh03
+0038_Gh04
+0039_Gi01
+0040_Gi02
+0041_Gi03
+0042_Gi04
\ No newline at end of file
diff --git a/tests/snapshots/test_cellpack/test_load_cellpack/cif/chain_id_unique.txt b/tests/snapshots/test_cellpack/test_load_cellpack/cif/chain_id_unique.txt
new file mode 100644
index 00000000..d5221b51
--- /dev/null
+++ b/tests/snapshots/test_cellpack/test_load_cellpack/cif/chain_id_unique.txt
@@ -0,0 +1 @@
+['Cv0', 'Cv1', 'Cv10', 'Cv11', 'Cv12', 'Cv13', 'Cv2', 'Cv3', 'Cv4', 'Cv5', 'Cv6', 'Cv7', 'Cv8', 'Cv9', 'Ed0', 'Ed1', 'Ed2', 'Ed3', 'Ed4', 'Ed5', 'Ed6', 'Ed7', 'Ed8', 'Gb0', 'Gb1', 'Gb2', 'Gb3', 'Gg01', 'Gg02', 'Gg03', 'Gg04', 'Gg11', 'Gg12', 'Gg13', 'Gg14', 'Gh01', 'Gh02', 'Gh03', 'Gh04', 'Gi01', 'Gi02', 'Gi03', 'Gi04']
\ No newline at end of file
diff --git a/tests/snapshots/test_cellpack/test_load_cellpack/cif/instance_names.txt b/tests/snapshots/test_cellpack/test_load_cellpack/cif/instance_names.txt
index 5d3869e3..9b85243b 100644
--- a/tests/snapshots/test_cellpack/test_load_cellpack/cif/instance_names.txt
+++ b/tests/snapshots/test_cellpack/test_load_cellpack/cif/instance_names.txt
@@ -1,43 +1,43 @@
-0000_Cv0.003
-0001_Cv1.003
-0002_Cv10.003
-0003_Cv11.003
-0004_Cv12.003
-0005_Cv13.003
-0006_Cv2.003
-0007_Cv3.003
-0008_Cv4.003
-0009_Cv5.003
-0010_Cv6.003
-0011_Cv7.003
-0012_Cv8.003
-0013_Cv9.003
-0014_Ed0.003
-0015_Ed1.003
-0016_Ed2.003
-0017_Ed3.003
-0018_Ed4.003
-0019_Ed5.003
-0020_Ed6.003
-0021_Ed7.003
-0022_Ed8.003
-0023_Gb0.003
-0024_Gb1.003
-0025_Gb2.003
-0026_Gb3.003
-0027_Gg01.003
-0028_Gg02.003
-0029_Gg03.003
-0030_Gg04.003
-0031_Gg11.003
-0032_Gg12.003
-0033_Gg13.003
-0034_Gg14.003
-0035_Gh01.003
-0036_Gh02.003
-0037_Gh03.003
-0038_Gh04.003
-0039_Gi01.003
-0040_Gi02.003
-0041_Gi03.003
-0042_Gi04.003
\ No newline at end of file
+0000_Cv0
+0001_Cv1
+0002_Cv10
+0003_Cv11
+0004_Cv12
+0005_Cv13
+0006_Cv2
+0007_Cv3
+0008_Cv4
+0009_Cv5
+0010_Cv6
+0011_Cv7
+0012_Cv8
+0013_Cv9
+0014_Ed0
+0015_Ed1
+0016_Ed2
+0017_Ed3
+0018_Ed4
+0019_Ed5
+0020_Ed6
+0021_Ed7
+0022_Ed8
+0023_Gb0
+0024_Gb1
+0025_Gb2
+0026_Gb3
+0027_Gg01
+0028_Gg02
+0029_Gg03
+0030_Gg04
+0031_Gg11
+0032_Gg12
+0033_Gg13
+0034_Gg14
+0035_Gh01
+0036_Gh02
+0037_Gh03
+0038_Gh04
+0039_Gi01
+0040_Gi02
+0041_Gi03
+0042_Gi04
\ No newline at end of file
diff --git a/tests/test_cellpack.py b/tests/test_cellpack.py
index caa15494..96c969f4 100644
--- a/tests/test_cellpack.py
+++ b/tests/test_cellpack.py
@@ -23,6 +23,7 @@ def test_cellpack_data(snapshot, file_format):
 
 @pytest.mark.parametrize('file_format', ['bcif', 'cif'])
 def test_load_cellpack(snapshot, file_format):
+    bpy.ops.wm.read_homefile(app_template="")
     name = f"Cellpack_{file_format}"
     ens = mn.io.cellpack.load(
         test_data_directory / f"square1.{file_format}", 
@@ -39,9 +40,9 @@ def test_load_cellpack(snapshot, file_format):
     ens.modifiers['MolecularNodes'].node_group.nodes['MN_pack_instances'].inputs['As Points'].default_value = False
     mn.blender.nodes.realize_instances(ens)
     apply_mods(ens)
-    
     for attribute in ens.data.attributes.keys():
         snapshot.assert_match(
             sample_attribute_to_string(ens, attribute), 
             f"att_{attribute}_values.txt"
-        )
\ No newline at end of file
+        )
+    snapshot.assert_match(str(ens['chain_id_unique']), f"chain_id_unique.txt")
\ No newline at end of file