As of this moment, what is your sysnand? turn off your console completely (not sleep mode), then turn it back on, and open settings and on the bottom right corner of the top screen it should tell you your firmware version. This is your SYSNAND. If it says anything above 9.2, then you're screwed. And you must wait until someone exploits systems that are at firmware versions 9.3 and above. If it does say 9.2 or lower, say like mine says Ver 9.2.0.0-20E, then it is supported. You can use your gateway, I recommend going to their website and downloading the manual and whatnot.
Emunand is basically a copy of your sysnand. Long story short, it is what people with firmware versions 9.2 and lower use to prevent irreversible damage to their 3ds. First, you need to have a system with firmware 9.2 and lower like I mentioned above. Once you satisfy this requirement then you can use gateway. If not, then you can't.
Think of it like an onion, emunand is the outermost layer and sysnand is the inner most layer. If you mess up your emunand, you can just peel off that layer and try again. But if you mess up your sysnand, you're done since there are no more layers. Also you need to be able to have the right sysnand first before you can use the emunand in the second place. In this case sysnand 9.2 AND LOWER. So check that first. If your 3ds has sysnand 9.2 and lower then we can talk. If not, then you're better off buying a Sky3DS.
