i have played around with alot of the ebay relays and autoclosure modules.
I'm not an electrician, but i know a little about cars, and not afraid to give things a go.
If you're looking for FULL autoclosure on the windows, then don't bother... i've wasted £100s of pounds finding and developing a unit that would work sensibly. But none do.
First few units I used refused to power down... draining the battery.
Other units would continually retrigger to wind the windows up.
More recently, a module that was SO close to working, worked in a very unpleasing way. 1 window at a time... and then failed every time it got to the drivers door.
However, you don't have to take my word for it... try it yourself.
You will need to intercept the +12v line between the door switch and window motor, from each door panel. This will connect to the brown and blue from the modules.
You will need a +12v continuous feed (drivers kick panel) and an -0v earth (chassis).
Then you will also need to trace the trigger wire from the loom (drivers kick panel).
This is by no means your definitive guide, just to show you sort of skill is required when experimenting.
NB: ATTEMPT AT YOUR OWN RISK!
Finally ensure that you have a fire extinguisher handy, lol.
Have fun :D