Well if you still are looking for an answer.
TransactionNumber, TransactionItem and TransactionID are some variables of the framework.
- TransactionNumber identifies your current transaction count
- TransactionItem stores your DataRow value that you are processing in an iteration
- TransactionID is what you can use to identify your processing iteration. In this case WIID
1 is default handled
2 you may have already done and understood.
3 is what they are asking for in this paragraph.