I have been doing some checking and found that this change came about through a need to address a defect:
https://support.ca.com/phpdocs/7/5590/5590_r143_resolved_defects.html
CLRT-77011 (S2) - BPM-0519: Internal Process Engine Error. Contact your site administrator (Object with name ’’ refers to object ’’ bound to the instance ’’ is not found).
Synopsis:
Some processes of the customer is failing with a BPM-0519: Internal Process Engine Error. Contact your site administrator (Object with name ’’ refers to object ’’ bound to the instance ’’ is not found) error message.
Steps to Reproduce:
1. Create a new object: "Objeto Vinculado"
2. Create a new lookup attribute: "Resource that will receive action item" Use lookup: SCH_BROWSE_RESOURCE
3. Add this new attribute to the mais view of this object.
4. Go to Other Work object and create a new lookup attribute: "Objeto Vinculado" Use the lookup: OBJECT_LOOKUP_OBJ_VINCULADO
5. Add this new attribute to the view of the object Other Work.
6. Go to the lookup (OBJECT_LOOKUP_OBJ_VINCULADO) > Go to Query tab and click on Save and Continue.
7. Verify if in the next page (Parent Window) the Hidden Key is "odf_pk".
8. Create a new Process "You can give any name"
9. In the Object tab, Set Other Work object as the Primary Object Add "Objeto Vinculado" as a Linked Object.
10. Create a new step that send an action item to the attribute "Resource that will receive action item" of Objeto Vinculado object.
11. Create a new instance of the Objeto Vinculado object and select a resource for the attribute "Resource that will receive action item", select a resource that has no access rights to Other Work object.
12. Create a new instance of Other Work and in the Objeto Vinculado attribute, select the instance created in the previously step.
13. Access Processes tab and execute the process created.
Expected: Process continue the workflow normally.
Actual: BPM-0519 error message and process failed.
We realise that relating this defect to that impact isn't at all going to be an obvious one, and are planning to create a knowledge document to help bridge them, however this change is intended and for this reason.