Quantity of water
The pressure pan manufacturers (electric, electronic, stove-top) all recommend 1/2 cup more water than is desired in the final recipe as a guideline when cooking a new, non-pressure pan recipe for the first time.
If a recipe is moisture sensitive, then it's useful to put a small rack in the pan, pour about a cup of water, place the food to be cooked in a bowl and place that on the rack. Super heated steam doesn't contribute moisture, so you won't need a lid (but may want to use one). Problem solved.
If you want to cook something that tends to foam, be sure to use lots of oil or butter. There's a myth that one mustn't use oil. That's nonsense left over from the bad old pressure-fryer days when people used oil under pressure to cook in pans not designed for it.
Feel free to use three tablespoons or more of oil or butter for bean/ lentils. Two tablespoons for a big bowl of porridge made of any of the usual grains (this is where the bowl on the rack really shines).
In keeping time for new recipes, follow any pressure pan recipe that is similar. That will be close enough. Generally speaking, once you get above two potatoes, it's going to be faster than a microwave oven would be, so when cooking things which don't like overcooking, be sure to check early.
Shock cooling is normal, only meats and canning produce are left to cool 'naturally'. This is one of the worst mistakes (next to the no oil nonsense) on many modern websites.
Never fill the pan higher than the manufacturer says.
I put a teaspoon of white vinegar in the water when using our magnesium-aluminium alloy (Model 40) pressure cookers and they never discolor. Wash with an SOS pad and DAWN. Never, ever, under any circumstances use Scotchbrite green or put in the dishwasher.
