How to grant user User Points equal to certain field's value / calculated value?
I finally found a solution! I completed the second scenario (the amount of User Points is calculated) successfuly! Apparently, the User Points module didn't know that the calculation was an integer. Therefore, I had to add an extra action Convert data type: Target type: Integer, Value to convert: [result], Rounding behavior: Always down. I called it 'total' and granted the user this amount of User Points.