1. Make a reservation in that area, and open it in the admin area. There you can see the full calculation and find out what’s wrong with your setup.
2. It takes % of the base price as there is nothing to take percentage of at that stage of calculation. Better use fixed amounts.
3. Found a bug that the standard requirements wouldn’t be overwritten. Will be fixed in next beta (release end of the week)
4. They order correctly when using the same priority.
5. That’s where priority comes into play. Make two filters checking the length of stay, one with condition 20 and the second with condition 1. The first is extra charge 0 and the second your price set to per person. So if it’s 20 days or more they wont get charged.