That means they just aren't downloading in the first place. Can you try downloading the apk on a different device and transfering it to your X to see if it will install? Also, have you tried multiple apks or just one?
i've tried several ones and none of them are working :/
i remember that jelly beans had an device manager app or so preinstalled. so you could connect your device via usb and copy the apk on the device and through that device manager app you could install the apk.. i can't find that app on kitkat..