Hello friend! I'm sorry this is happening to you. The reset button simply uses the command "reset." This will restore the cvar (something that stores a number, in this case, the third person range) to its original setting. The console command it uses is "reset cg_thirdpersonrange." You can find all this by opening the .pk3 and going to ui/camsp.menu. I would be curious to see if you were to edit your cg_thirdpersonrange setting in the console (to something random), then manually type "reset cg_thirdpersonrange" to see if it works as expected. If so, it would be some strange bug with the mod. Otherwise, something else is causing the issue. Good luck!