Blender removed the "Keep Custom Normals" checkbox on the Triangulate Modifier in 4.2, and that is now the default behavior. This causes exports with SourceOps to fail, since from what I can tell it tries to set that checkbox that no longer exists:
Python: Traceback (most recent call last):
File "C:\Users\Username\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\SourceOps\addon\ops\export_meshes.py", line 31, in invoke
error = source_model.export_meshes()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\Username\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\SourceOps\addon\types\model_export\model.py", line 88, in export_meshes
self.export_mesh(self.armature, objects, path)
File "C:\Username\Username\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\SourceOps\addon\types\model_export\model.py", line 113, in export_mesh
self.export_smd(armature, objects, None, path)
File "C:\Users\Username\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\SourceOps\addon\types\model_export\model.py", line 126, in export_smd
smd.from_blender(armature, objects, action)
File "C:\Users\Username\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\SourceOps\addon\types\model_export\smd.py", line 435, in from_blender
self.triangles.from_blender(self.lookup, armature, object)
File "C:\Users\Username\AppData\Roaming\Blender Foundation\Blender\4.2\scripts\addons\SourceOps\addon\types\model_export\smd.py", line 358, in from_blender
mod.keep_custom_normals = True
^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'TriangulateModifier' object has no attribute 'keep_custom_normals'
Blender removed the "Keep Custom Normals" checkbox on the Triangulate Modifier in 4.2, and that is now the default behavior. This causes exports with SourceOps to fail, since from what I can tell it tries to set that checkbox that no longer exists: