The purpose of the NefMoto software is to enable Read / Write of a factory standard ECU via the ODB2 port. Discussion of GIAC etc. tunes are due to people reading them out via other means because most commercial tunes have blocked OBD2 read functionality.
The origin of the BIN file doesn't affect NefMoto's ability to flash it to the ECU so it's important that the file is compatible with the target ECU and it's checksums are correct.
Take a look at the WIKI
http://nefariousmotorsports.com/wiki for lots of lovely words.