Based on official release notes and community feedback, V2.8.1 was a minor but critical patch released over the older V2.8.0. It was designed to fix a specific, frustrating bug:
Yamaha Expansion Manager is a free desktop application designed for Windows and macOS. Its primary purpose is to allow musicians to manage expansion content for compatible Yamaha keyboards. With YEM V2.81, you can: yamaha expansion manager v281 for windows 10 81 best