I wasn't sure if the 4 GB limit "discovered" FAT32's limit or if it was a MP3 format issue I think it's based on commodity single-layer DVD's being the storage

I wasn't sure if the 4 GB limit "discovered" FAT32's limit or if it was a MP3 format issue I think it's based on commodity single-layer DVD's being the storage medium, since the process seems to produce ISO files for burning, which might imply ISO 9660 limitations. Although, there's MPEG/DVD mastering software in use, which would (probably) be smart enough to fragment assets, and chain them together for continuous playback (considering the availability of dual-layer 8GB recordable DVD's). The images also note a Thinkpad is in the mix, which might imply Windows XP (or newer), and possible access to NTFS partitions, which permits files of 2^64 bytes.