Just came across interesting files at
Yamaha QY70 Data Filer Windows 98 or later (32-bit) 1 MB
Download Link
Yamaha QY100 Data Filer Windows 98 or later (32-bit) 4 MB
Download Link
Yamaha QY100 Firmware Update * Version 1.37 1 MB
Download Link
In case you are interested
Brahim @ Singapore
Brahim HAMADICHAREF