I have the K95 RGB Platinum keyboard with firmware v1.07.123, Glaive RGB mouse with firmware v1.07.123 and the H80iGT cpu cooler. iCUE software version is v3.9.93
The back and forward button keep failing to work for me to. And I have to say that the iCUE software for this is the worst program that I have ever used for hardware, it is not user friendly at all and need to be dumbed down a lot to be usable.
And like CoolRaoul, the back and forward button start to work when you exit iCUE software.