Here are some things you must remember before configuring things your own way:
- fluxbb folder should be named "fluxbb"
- fluxbb folder must be inside your root fluxcp
- addons must be in fluxcp\addons folder not in fluxbb\addons folder and must be named "fluxbb"
- then apply the patch with git or you can do it manually.
To better understand how the addon works. Cheers!