Does decrypt9wip let you dump a cart to a cia using only your 3DS, no PC needed? Because it was my understanding you had to dump the cart as a decrypted rom, copy it to your computer to convert it to cia format, and then copy the converted cia back.
The most recent update of Decrypt9 added cartridge dumping features, the homebrew in the OP is simply that exact menu taken from Decrypt9's source and built as a standalone app.