Seriously though. You need an XML for Riivo to work, go into the vaults and search BeyondYou's XML, it has the same setup as what Gecko has, just read the readme in the download to learn how to set it all up
If im not mistaken, that sword is a article, so if thats the case, take a normal Cloud Vertex and simply replace his normal sword with the one found in that mod
That XML has alot of issues with loading files. I strongly suggest you use BeyondYou's XML.
Place the XML file in the root of your SD in a folder called "Riivolution", not where you store the eboot of Riivo itself in the Apps folder. Then go onto the Riivo Wiki and download the codehandler XML so that you can run codes with Riivo. Make sure when you open Riivo that you set the code set to IV, and not anything else.
If you are playing a basic brawl match with Gecko (since with Riivo, it applies the texture to all players using that texture) and someone comes in with a custom texture that you have, they have that texture. If someone comes in with a model known to desync and you have that model as well, it will desync no matter what. Now if all players had that model, then the match would not desync, since all the players have it. The possibilities of that happening however, are slim