A sequence of events that I would not expect:
1. Create new MCF
2. Attach 840D and Basic CCFs
3. Simulate Machine Code File opens fine
4. Copy transformations from 840D to MCF
5. Delete transformations, bringing the state of MCF back to the end of step 2
6. Simulate Machine Code File brings up errors
7. Delete that MCF
8. Create a new MCF
9. Attach 840D and Basic CCFs
10. Simulate Machine Code File brings up errors
It seems that with these steps I have now modified the CCFs somehow?
Sorry didn't got that :-(
May the other repost will help find a solution for your actual use case.