CBCR reporting entity information

Content

I am adding entity information to the Reporting Entity Information. There are 10 TRCS entries. I added additional entries and added data.
I tried to add the TIN # and TIN Issued by, however I could only add this to Entry 1 and not to the other 9 TRCS seeded entries or the additional entries added.
I could add information using the In Code and IN Issued by.

So the question I have is how is Reporting or Constituent Entity data to be loaded.

1) Is all data loaded to Entry 1 only or to multiple Entries.

2) What are the other entries used for, since they do not seem to allow complete data load.