C4C: SAP Cloud Application Studio error "Object instance creation of action rejection implementation class failed"
In case you're facing a C4C dump (500 Internal Server Error), create an incident from it and find that the the Incident Context => /SAP/ABAP/RuntimeError file shows the error "Object instance creation of action rejection implementation class "<PDI solution namespace>_CL_ACTION_VALIDATION" of action "<PDI solution namespace>_<ID>" on node "ROOT" in BO "<BO>" failed" - you have to do a full solution activation to resolve the issue.