Custom firmware (custom ROM) developers used tools to unpack RPKG files:
The final official firmware for the N70 is . If you are searching for ROMs, aim for this version to get the best stability and the latest bug fixes for the music player and camera interface. Euro-1: Best for English and Western European languages. APAC: Required for Asian language support. nokia n70 rom rpkg
Offset 0x00: 'R','P','K','G' (magic) Offset 0x04: Version (2 bytes) Offset 0x06: Header size Offset 0x08: Payload size (uncompressed) Offset 0x0C: Payload size (compressed) Offset 0x10: Number of files Then follow file entries (name, offset, size) Custom firmware (custom ROM) developers used tools to
This is the most crucial part. Flashing the wrong RPKG will permanently brick your N70. nokia n70 rom rpkg