If you are looking to modernise your experience, ensure your "Option File" is placed in: Documents\KONAMI\Pro Evolution Soccer 6\save\folder1 specific tactical guide for a certain team, or are you looking for installation steps for a modern PES 6 patch?
Based on existing PES 6 Expert Guides and community documentation, an EPUB file of this nature would likely include: Releases · NicoLiendro14/pes6-trainer - GitHub Pes6 Trainer 11.epub
A real eBook is usually 1-10 MB. A disguised trainer is often 200KB to 2MB. If Pes6 Trainer 11.epub is around 500KB–1.5MB, it is almost certainly a renamed .exe . If you are looking to modernise your experience,
Potential structure: