The most confusing setting is the 'ENGINE' setting, you can choose between Comfort/Eco/Sport/Cupra.
None of these modes change anything to do with power or actual noise coming from the exhausts.
Comfort is a standard linear style throttle response, Eco is similar but it will make the throttle slightly less reponsive and also coast the gearbox in neutral when you are moving but off throttle to try and save more fuel.
Sport makes the throttle response sharper (basically it piles on the revs faster with less push on the throttle). It also adds the Soundaktor (Fake noise piped into the cabin).
Cupra is basically the same but it makes the throttle a bit more sharper and pipes a different fake noise into the cabin.
If the car is turned off with the engine set to Sport or Cupra it will default back to comfort on restart, you have to re-select the profile you want to reactivate it.
Things also get more confusing if you have DSG.
DSG and Engine settings are 2 different settings, how the DSG is set has more effect on the car than the engine setting.
Drive mode is made just for cruising, there is a flat spot on the pedal from standing which is make you set off smoother and it will gear up as soon as possible. You can still switch over to manual mode and pick your own gears though.
Sport mode idles the car higher and also idles the turbo ready for a more responsive launch from standing. The gearshift holds onto the gears also. This also can be set into manual mode which imo is a better way of using it, Sport auto holds onto gears too long. Sport mode also makes the gears bang in harder and you can feel the changes, also this is the mode you will get the actual car noises, DSG farts and pops. (I've noticed farts from mine at 5.5-6K changes in Sport but no pops).
You can change the DSG inbetween Drive and Sport anytime no matter what your Drive Profile settings are. Setting a preset or individual setting where your Engine is set to Sport or Cupra will then default the DSG to Sport but you can still just knock it back into drive and it will keep the engine setting on.
I'll add more about the other settings later!