The software for (Rapoo) gaming mice can be downloaded directly from the official regional support sites
Most users download the software but ignore firmware. Firmware lives on the mouse’s microcontroller; the software is just the interface.
Rapoo Europe: Driver Overview (Best for finding specific EU-market models like V20Pro or VT9Pro). 2. Common Software Versions
For some older or more generic VPRO-labeled mice, even finding OEM software proved impossible. In this case, the solution was a community-created, open-source program called "OEM Mouse Button Control" . While it lacked the flashy UI of official software, it was a powerful tool that could communicate with the basic USB HID protocol of almost any generic mouse, allowing for button remapping.