First lap: *absolutely* no passing in the first turn. Just wait until "la Puerta de Alcalá."
Have a few thoughts on Madrid but first I'd like to suggest that this needs to be better defined. You have a whole grid full of cars, all pretty much the same speed and there's no way that some of them aren't going to be side by side entering the corner. Things are happening so fast, it's going to be impossible to keep track of everyone around you and what they are doing. If one of them brakes just 10 feet too soon, the car beside them is going to go flying by them, looking like a pass.
If there is a specific first corner rule, I don't think you can avoid two wide heading into there, at least among some cars, so I'd prefer that we acknowledge that that is inevitable and just place a higher burden on allowing enough room for the car beside you to get through the corner. In other words, something like, "
First corner, first lap, is very tricky. It's inevitable we will have some two wides there, take extra caution that you leave a lot of room there, if you don't and cause someone to hit the barrier losing positions, you may be severely penalized and have your finishing position equated to lower than the person you put into the guardrail if you should finish in front of them."
Of course in any case, the usual GTP Contact Concessions apply and you are expected to pull aside and let the person you forced into the guardrail past you, when it is safe to do so, within a lap or so. If you are in doubt as to whether you caused an incident in that corner or any other, continue on as usual and a penalty can be applied post race upon review.
We did a Cappuccino Race at Madrid one time and had a 9 car pile up in the final hairpin in one of the smallest cars in the game. One car spinning there or hitting the guardrail on the inside, can stop the entire field. Accidents happen sometimes but one thing you might want to consider is to
declare the final hairpin one consecutive corner. In practice that means that you can attempt a pass entering the corner and just hold your line as usual. In that case, all the usual rules about corner rights and giving room apply from GTP.
But once you enter the corner following someone you can't pass them unless they make a major error warranting a pass, meaning a spin, a near spin, or running into the guardrail. Simply getting a few feet off the racing line because someone came in too hot, does not warrant a pass attempt. If we allow guys to make risky pass attempts halfway through the hairpin, incidents will probably follow. Following behind someone who makes a slight error will cost you a couple of tenths at most, so it's not a big deal.
One other thing you might want to consider is, the road leading up to the hairpin is quite narrow, for a couple of hundred metres at least it's barely wide enough to fit two cars. You might want to designate that a
"high risk" passing zone, meaning that passing there is legal if you think it's safe, but if you get side by side with someone and run them into the guardrail, extra penalties may be applied to you on top of the usual contact concessions required by GTP Rules. This doesn't limit anyone's racing in any way.
Madrid is a very tough track to race on, but if everyone uses their heads combined with a couple of minor rules to enhance safety and clean racing we should be alright. I think the worst problem drivers are gone now and the rest of us are pretty much on the same page.