Look for a file named RELEASE_NOTES.TXT inside the ZIP. If missing, check support.uni-electronics.com/[model]/bios23-changelog.html .
You downloaded the wrong board revision. Fix: Double-check motherboard model (e.g., UNI-H81-V2.0 vs V2.1). The “uni bios23 zip” for V2.0 will not work on V2.1. uni bios23 zip
Then the content inside uni_bios23.zip might be: Look for a file named RELEASE_NOTES
: Allows users to listen to game music tracks without sound effects. switch between Console and Arcade modes
[Link]
Created by Razoola, this BIOS is a popular modification that allows players to change regions, switch between Console and Arcade modes, and access a built-in cheat database and jukebox. Key Features of Universe BIOS 2.3 Region Switching