How do I Create a wave system?

Edited:

How do I create a wave system that allows me to do something like..

1. set the type of enemies that spawn

2. set each enemies spawn rate

3. set each enemy points

4. set how many of each type needs to be killed to advance to the next wave

5.I would like it to use an array so that I can define multiple waves at a time

6.I would like to be so that when the wave reaches a number it uses the array to set 1,2,3,and 4

I want the wave system to be virtually infinite

so that is why I would like to use an array or something

I'd be inclined to have an object which is not actually visible to the player which defines the wave, then write a function which launches that wave. The difficult bit is (3) ; for that I would have a string in the object which is a function which is called which calculates an objects position. If you put all your enemies in a family it should work okay.

last time I used the function plugin it crashed I can try doing it again though