Even though it is a bit old now, I still love my Asus N56VJ laptop. It has nice hardware quite capable of running Window 10 and it does that almost flawlessly. Only thing I found misbehaving is button for disabling touchpad (
<F9>). On laptops I previously used (mostly HPs) I wouldn't consider that a huge issue. However, through great efforts, Asus has managed to manufacture such a lousy touchpad that I consider disabling it a mandatory function.
To get button working on a fresh installation of Windows, first step is to install the latest ATK Package followed by restart (important). On its own this does nothing but enables proper installation of Asus Smart Gesture touchpad application (followed by another restart). Only once both of these are installed, you will get
<F9> working again.
Unfortunate news for Windows Insiders is that functionality will disappear as soon as new build is installed. And no, you cannot just repair applications. You will need to fully remove both ATK Package and Asus Smart Gesture followed by computer restart. Only then you can follow the original procedure once again and have the button working.
I guess I cannot expect wonders by using the latest Windows OS with now aging laptop, but I find this behavior most peculiar and worthy a frown.