95 Maxima Integrating factory+aftermarket alarm

Here's my dilemma. I have 95 Nissan Maxima with a factory alarm. It locks/unlocks doors (driver or all 4 doors it pressed twice, pops trunk, rolls down windows, and can turn on dome light.  Im looking to buy  a Crimestopper cs-2015fm. My problem is that Im not sure if I'll be able to keep the features from the factory alarm + the features the Crimestopper has with one control. What I mean is, can I combine the features from the factory alarm with the Crimestopper and only use the Crimestopper control. Or will I have to keep both alarms in order to keep the features I currently have. I have found several helpful installation sites that deal with the basics, but they dont show I would go about installing this alarm while keeping the factory alarm features. Could this be done? Would I need any extra relays? Any help or advice would be greatly appreciated. I hope this made sense.

although i'm not familiar with crimestopper products, as long as the unit has additional outputs you can make the alarm do whatever you want.  the factory alarm arms and disarms with the lock wires in the driver door - easy integration there.  as far as rolling windows up and down, do your windows roll up/down when turning and holding the key to lock/unlock in the driver door?  if so, this will be an easy integration as well - if not, you merely need to purchase a window control module.  all very do-able items.

Actually the windows roll down (and only down) when I press and hold the unlock button on my control.  So usually when Im getting close to my car I just press and hold the button to roll down my front two windows to air out the car (works great in the summer). So do you know how I would get that to work?