WARNING: It has been brought to my attention that MAMEDEV, the team that is owed thanks for the wonderful emulator, has been updating the NEO·GEO sets in recent updates. So, if your MAME ROMs are current, then you may find some games not working whatsoever. Hopefully, the upcoming v.2.1 (no date announced) will mirror those changes. Please heed this warning should you experience any non-working games. Thought I'd toss a helpful guide on how to use NEO·DS in here, since it's been asked before, and the tutorials that I've found do not really show much. Here's how it goes. Also, do NOT ask where to acquire any ROMs. This act alone violates GBATemp's policies. As with DS and GBA ROMs, they too are protected by copyright laws. Thefefore, you may not legally possess any ROMs unless you physically possess the MVS cartridge(s) of the games that you wish to run using NEO·DS. 1. Download and extract the NEO·DS download somewhere you can remember. You can get the latest version (v.2.0 at the time of writing this guide) here. 2. You need to have the latest and complete MAME ROM set(s) in zipped form. Make certain that they are named correctly beforehand by the official build of MAME's standards, not NeoRAGEx or another emulator's compatible set. 3. In the folder, /NeoDS/NeoDSConvert/, copy the neogeo.zip within and leave it there. Do not decompress. 4. Copy the ROM you want to convert into the same folder. Again, do not decompress. 5. Using Command Prompt, navigate to the directory and type the following: neodsconvert -biosX romname Example: neodsconvert -bios3 cyberlip X is the variable for which region you want the ROM to be. Here's what they are: 0 = Europe MVS (Ver. 2) 1 = Europe MVS (Ver. 1) 2 = US MVS (Ver. 2?) 3 = US MVS (Ver. 1) 4 = Asia MVS (Ver. 3) 5 = Japan MVS (Ver. 3) 6 = Japan MVS (Ver. 2) 7 = Japan MVS (Ver. 1) 8 = Universe Bios* 9 = Debug MVS* 10 = Asia AES* 11 = Japan AES* NOTE: Not all BIOS files, such as the Universe BIOS, are in the official MAME's neogeo.zip. You will have to look elsewhere for those files should you wish to use them. You will need to add them into the neogeo.zip prior to converting. NOTE: If you are trying to convert a title that is a clone (different version, bootleg, hack) of a game (ex. SNK vs. CAPCOM SVC CHAOS Super Plus (bootleg)), you need to have both the parent ROM (svc.zip) and the clone (svcsplus.zip) in the directory. To find out which are parents and clones, go here. 6. A new file, romname.neo will have been created. 7. Repeat as you deem fit for other games. 8. When done converting, copy the file, neods.ds and the .neo file(s) to the root of your flash memory. NOTE: If your flash card does not possess automatic DLDI patching, do so before you copy neods.ds onto your memory. 9. Play! NOTE: Not all games are running perfectly, as the author has stated this before. Also, if a game isn't working after conversion, try a different BIOS setting. I hope this helps anyone having issues with conversion and operation.