You'll have to install their blue card fix.cia to use it. But you'd be better off buying a r4isdhc dual core 2016 for like $15. Works on all 3ds update versions with no patching required.

 

Yes you can use the blue card just fine, I'm using mine too and I too have Luma3DS with A9LH.

 

Have you done any modifications to something called TWL_FIRM? If not, skip part 1 and go to part 2. If you don't know for sure, start at part 1.

Part 1: To use the Gateway Blue card we need an unpatched TWL_FIRM, otherwise it interferes with the patches Luma3DS uses.
As per Luma3DS wiki:

Part 2: Preparing the Gateway Blue card for use

Sometimes the 3DS may not recognise the Blue card immediately. I have found you need to push the card a bit further into the slot and then it will work. Confirmed working as I'm using my Gateway Blue card to play Dragon Quest at the moment on my A9LH Luma3DS N3DS

 

This should be bumped for users who skip the TWL part of the Plailect guide.

 

Not to revive and old thread but just wanted to say that I followed the 3ds.guide today and all went well. Wanted to play a NDS game and just plugged in my Gateway blue card and it worked without doing anything special. I am running Luma 6.6.

 

Is a cart still required to play NDS games via Luma or can they be installed via cia somehow?

 

I wouldn't bother having nothing but the best when it comes down to DS flashcarts. Save games or getting stuck halfway through the game is worth more than twenty or thirty dollars.

Gateway blue card is meant to do its job (mset) and not much else.

 

Brick code never ever ever existed on the blue card, only the red card related launcher.dat and it was only for a while until they shot themselves in the foot with it by causing a community uproar. The blue card is an Ace3DS clone that can run a modded version of, I think it was AKAIO? You don't need to worry even though Nintendo blocked the card with update 6.2 because Luma unblocks it by itself. You don't need to patch anything.

The firmware for GW blue card has been posted here. https://gbatemp.net/threads/analysis-on-the-gateway-3ds-blue-cart-updateable.357103/ Get the _DSMENU.DAT and game.dldi files from the thread and replace the ones provided by Gateway. Bonus, get yourself an up-to-date copy of usrcheat.dat too. It should be 13MB and as always enjoy your new DS flashcart.

I think an ancient scare thread on Maxconsole that keeps popping up in Google search results from the time of GW bricks is keeping this idea coming back like a zombie.

 

gw_installer.nds can be removed, it is only ever useful for installing the MSET exploit. If you have A9LH installed you don't care about it at all.