After releasing version 1.3, dev $n!pR has released another update of his app PKG Toolkit GUI. This new update makes use of SCETool for ELF and SELF file decryption and encryption.
He has also added support for the latest CFW available (4.21, 4.30). Another of the new characteristics is the fact that you can now create Debug and Retail packages. It also automatically detects the TitleID of a package and also adds an extra tool called AllUnpkg.