Why have you 2° Camber Angle in the rear and 1.5° in the front? I never saw different Camber Angles on one car!

On most of my set-ups I always use more camber in rear, better rear traction.
Higher camber link keeps the car more flat and gives smoother cornering.

I have in the front 4.5mm Arm Spacer. What does change if I put 0.5mm more under, to 5.0mm?

In the rear, i drive with the 1XA-1D blocks. What does change if I change to the E-Block. I see very often the E-Block in the rear!

1XA - 1D is good for stock, in mod you need more toe-in.

When I change in the rear from 1.5mm to 0.5 Wheelspacer, get I more steering?

When you make the wide more narrow you will increase grip but less stability front and rear.

Ed: A few things I noticed over the standard base, if you wouldn't mind explaining the reasons behind them

1) Raised front roll centre (0.5 and 1mm shims). I understand the reason for the difference to get the anti dive, but was it a case of trying to reduce the front grip a little? or improve the reaction?

I raised the front to get a smoother feeling in the round corners of the ETS track.

2) 2.5mm lower deck?

2.5mm chassis works also better on high speed track like this weekend, better cornerspeed.

3) Shocks in one hole all round. I guess your were looking to slightly numb the initial reaction? This change working in conjunction with the lower deck maybe?

Marc ran all weekend with his shocks one more in, so I tried it on sunday morning and improved laptimes.