Plutonium

Something about my Ryzen CPU seems to not like the older Call of Duty games, including World at War especially. My frame rate and performance are perfect, but my mouse movement is really jerky and stuttery. Turning off multi-threading seems to be the only way to fix it. I do this in the non-Plutonium version by finding the configuration files and adding the line 'seta sys_smp_allowed "0"' to them. The problem is Plutonium seems to revert this change every time I launch it, even when I set the file to read-only. I'm pretty sure I'm altering the right files, found under AppData/Local/Plutonium/storage/t4/players. Basically, I need some way to keep that value set to 0, or possibly set it at launch via a launch argument, but I'm not sure where I would put it, considering it all runs through the Plutonium launcher.
Changing options related to mouse smoothing and multiple GPUs doesn't have any affect for me. I also tried forcing the game to use my integrated graphics instead of my Nvidia GPU. Seemingly, that config line/launch argument is the only fix for me, so I would appreciate any help. Thanks.