Which ASMedia USB 3.0 driver did you use, the one from the beta list on your board's download page?
Try this driver which is provided with ASRock Z97 boards: 188.8.131.52/downloadsite/drivers/All/USB/ASMedia_USB3(v184.108.40.206).zip
Drivers for USB 2.0 have been provided by Windows at least as far back as Windows XP. If your USB 2.0 ports aren't working, there may be another reason for that. What do you see in Device Manager about the USB 2.0 ports?