Is it possible to download a game update in emunand, then use the update in classic?

I'm on the same boat, I just downloaded the update on emuNAND and will update my sysNAND to 8.1 using the cartdrige itself (I keep rolling bakc between 8.1~4.2 using Gateway Nand restore tool), I will post results, BTW both of my Nands are linked.

 

As far as I'm aware, the update should wrk without question but the update needs to be the same region as your console region.
Make sure that the region is correct and you shouldn't have any problems

 

Couldnt you use an update .cia in sysnand?

 

My updates work in sysNand so idk what your issue is...

 

Classic Mode is also emuNAND, so it should work without problems.

 

What I suggest you do since his DS is on 8.1 is download the update and play in sysnand, works for me

 

First make sure the update is the same region as the game as already mentioned. Is smash a cart, rom or cia? Since you are playing from classic mode I assume it is a cart.

Try getting the update from in-game while in classic mode and see if that works.

There are places you can download the update and install it as a cia with dev menu or BBB, but that should not be necessary.

You could try what pokemoner2500 said and that should also work but is not really a long term solution. There is a problem that needs to be addressed.

Another step is to backup everything including emunand using the emunand tool and then start with a fresh emunand and see if that solves the problem.