This is small program for SetItem edition.
Using:
Just drop SetItem.SData file to the program.
Decryption is not required.
Output:
Encrypted SetItem.SData.
Just put this file to the Data without any changes.
Screenshot:
Requires

to run.

P.S.
I did not test this program in the game.
There may be problems with line breaks (just a theory).
Write if there are any problems. I will fix it.