Hey man, I was kinda confused about these things to but I read a post about customising your HUD somewhere. Basically you have to go to the main options and select edit HUD, when in that menu select HUD Lite (I'm not on my PC now so bear with me). Some people have mentioned that you must manually save (with the dpad on consoles) after each change & it should work. It worked for me.
With regard to downloading tunes, I stumbled on this yesterday. In time trial mode you can download someones tune after you select their ghost to race against.
I hope this helps