This appears to be a bug in the Component Options dialog of Dynamic Components. I can reproduce by writing an attribute with a point array to a custom dictionary.
model = Sketchup.active_model
component_def = model.definitions.add
component_def.entities.add_cpoint(ORIGIN)
model.entities.add_instance(component_def, IDENTITY)
component_def.set_attribute("my_attributes", "point-array", [ORIGIN])
I’ll log a bug but Dynamic Components isn’t very likely to be patch soon as it’s an old code base with a lot old tech debt, and numerous other extensions rely on its internal functionality and risks breaking if we touch anything.
For now my only recommendation would be to try to write the attributes to the component instance or a nested entity, if possible.