Depending on how hard you drive the car, you may be dropping the pressures a good bit more than 4psi
Best way (until you get familiar with what the cold pressures need start off at) is to do a couple of laps, come in & drop the pressures to the recommended cold pressures. Do a couple more laps & repeat until the pressures stabilise. I usually find that means 8psi let out of the rear & about 4psi out of the front. If the car is understeering in slow to medium corners, let a bit more out of the fronts. If it's oversteering in fast corners under power, let a bit more out of the rears. You'll soon find the optimum for the car if you do it methodically. If you can find somebody with a pyrometer, try to borrow it and aim for a reading that is within 10 degrees across the width of the tyre. Take a torque wrench (or ask to borrow one at the TD) and ensure that your bolts are done up to 130nm BEFORE going on track. Check again after the lunch break. If you have locking bolts, take them off for the day & replace with regular ones - I've lost count of the number of people who've broken that stupid bolt key that seems to be made out of the stuff they made Matchbox cars from!
Brakes should be fine so long as you apply them firmly and for the shortest time possible to slow you for the corner ie. don't ride them for 200 yards if applying them firmly for 50 will get the job done. Engines never overheat IME.
Regarding camera mounts, most trackday organisers will not allow window suction mounts, gaffer tape etc. They want to see a proper mount secured to something that won't move in the event of a crash. I have a simple mount permanently clamped to my roll cage. You can sometimes get away with a less than solid mount if you're using a bullet camera attached to a solid-state DVR that's tucked away in the centre console arm rest.
Paul's point re: oil is a good one, but assuming you are not in a Turbo or GT2/3, be aware that oil surge & starvation can afflict the normal M96 engine.
If you can, get a bit of instruction early on in the day. This can be invaluable for getting the lines & braking points right & will make the rest of the day far more enjoyable.
Have fun!