So, if you're fine with that, in order to flash NTRBoot to an ARDS ME you'll need:
* ARDS ME, complete with USB Cable and Code Manager (& drivers) installed on a PC
* A console that can boot your Action Replay (DS/DS Lite)
* A flashcart - **this is currently REQUIRED**, as we need to trick the Code Manager into thinking that you own a regular ARDS. You could also try to use the ARDS ME's Media Player function to boot a ROM (yes, it can do that, as long as it isn't a commercial ROM) but I haven't tested it.
* Action Replay DS 1.71 Firmware file ([download link](
http://uk.codejunkies.com/support/article.aspx?article_id=434))
* A HEX editor
* NTRBoot for ARDS - the version I've linked here has been modified by me and doesn't need a patched Code Manager executable ([download link](
http://www.mediafire.com/file/d7oo6d2im5l1e76/ards_ntrboot.bin))
Now let's get started:
*(Optional, but highly recommended) Make a ROM backup of your ARDS ME.* If you don't have a shacked 3DS with GodMode9, you can use other tools, such as [NDS Backup Tool](
https://gbatemp.net/threads/nds-backup-tool-wifi.252623/).
1) Download the firmware file and open it in a HEX editor.
2) Delete the first 8 bytes (41 52 32 4D CC CD 00 00), then save and change the file's extension from .bin to .nds.
3) Copy that file to your flashcart, then run it. Wait until you get to the ARDS's main menu.
4) Eject the flashcart and insert your ARDS ME into your slot-1. Plug in the USB cable to your ARDS ME and to your computer.
5) Open Code Manager. The ARDS ME should instantly recognize your PC (if not, click the mouse button on the top-right on your DS. If it doesn't appear, you didn't insert your cartidge properly into the slot, so eject it and reinsert it until it gets recognized). Drag and drop the NTRBoot for ARDS file onto the title bar of Code Manager.
6) Wait until the firmware file is uploaded. Once it's finished, click "yes" when you're prompted to write the firmware to the ARDS ME.
7) NTRBoot has been installed on your Action Replay DS Media Edition. Congrats! Now place a FIRM file called ntrboot.firm on your 3DS's SD card and follow the guide.
There might be a way to install NTRBoot to the ARDS ME without using a flashcart, but I'll first need to do some extra testing and research, so that's it for the moment.