Note: Negative toe might still work in the qualifying environment. But all my setups will for now utilize positive or only slightly negative toe as I expect it to be the more sustainable solution.

The 992 GT3 R
Overall the new Porsche needs less steering as before and it's easy to turn too much. Maybe increasing steer ratio further can help to be precise.
Be careful on turn in. The tires likely need half a turn or more to build temperature on the surface and they are more snappy on entry when still cold. You can get them warm more equally by reducing camber and going for more positive toe. This will cost lap time in general, but might gain you time if the car is unrealiable on corner entries for you. While the car remains the crazy rotation off throttle, the center of that rotation seems far more in the center of the car now, than in the back, which makes it rotate more like a mid engine car. The rear doesn't feel quite as exposed on corner entry, and you get actually turn into the direction you want to go, instead of controlling a permanent slide. In Q the weight balance is still very far to the rear, hard to do anything about it. I tamed it as much as I could and again no negative toe needed here for (most of the) lap time. 
Especially in the race it feels very balanced and despite the wear on difference and front graining, it remained stable as far as I got into the stint. 

Oulton Park
Here on Oulton you have two options setup wise: Lots of downforce but drive around the kerbs, or reduce downforce, be slower in sector 1 and 3, but have a lot of room in the chicanes and simply use more track while also being less likely to die on a kerb. I went for the safer option, even though I think more downforce might turn out quicker over a single lap - if you can get everything right. Feel free to put the car lower and increase the rear wing as well for every 2-3mm you go lower. At some point the kerbs will start killing you though.

With the car sitting quite a bit higher that usual I didn't feel like making a lot of changes to the race set was needed.  Plus, with a rather stiff platform there also will be less change to the aero balance than with the softer setups on other tracks. 

Adjustments

• If too oversteery: Stiffer front spring, stiffer front roll bar, less rake. One click at a time.
• The brake bias is tricky. If it's too far forward the front will suddenly regain grip and the rear snaps. If too far back the rears might lock. Higher ABS here if you cannot handle it, but likely at a time loss. Clean trailing will pay off.
• higher preload can give more turn in stability, but will come with more nervous exits
• lowering front and adding rear camber might further stabilize the car
• lowering the caster also gives more predictability
• Some drivers might like a car with less rake for better drivability. It does not seem to be too problematic to lower the wing in turn for 2-3mm lower rear ride height.

Driving
The typical advice applies: Be gentle rather than aggressive, small inputs matter, keep adjustments subtle. Short shifting can work wonders here as the Porsche often runs out of rpm in the lower gear on exits and over bumps. The higher gear often prevents hitting the rev limiter accidentally, while offering more predictable traction. Focus on late apexes and test around with being aggressive on power in the medium and fast corners - there will be rotation from the diff and camber/toe settings that is quite nice.
The race setup will be a bit pitch sensitive in turn 1. You can dial it out with less front bump stop range, or generally less rake.

Tire pressures
Aim for 26.4 or more. Lower pressures might feel better in a slow corner, but its harder to hit the right slip. Go for 26.7-26.9 for solid support from the tire without surprises. For the race consider using 27.0 or more PSI which reduces the likeliness of losing pressure, but also still have some pressure left should you start losing it. Remember that the front pressures will drop anyway as the tank empties, so maybe even more there could be helpful.

Lap times
Q fuel: 12L
R: 96L