I have an Asus K013, an old tablet running android 4.2. As i have no use for it now, i want to downgrade it to android 4.1 as Wiimote compatibility is broken in 4.2+. However, I don't think it runs stock android (though I'm not sure) so I'm not sure how I would downgrade.
K013 (otherwise known as MeMO Pad 7 or ME176C) comes with Android 4.4 minimum, as shown on PhoneArena and supplied by the HelpDesk of ASUS themselves. Therefore, there's no lower version of official OS you could downgrade to. Since it's an Intel-based device, you won't be able to find custom ROMs for it either. Not to mention that there are only a handful of examples where custom ROMs can have a lower Android version than the lowest provided by stock ROMs.
TL;DR: No you can't.