To access the mod folder, simply right click the game in your Steam library, click manage, than click Browse local files. There is a folder called cxc.rte, open that.

Go to the loudouts.ini in the main mod folder and open it. Inside this folder, there should be a mention of a brain trying to pull from the base.rte.

Replace base.rte with cxc.rte. that will fix your issues. Also take note, you may replace all those names with whatever you like.