I'm not positive on this one, but check with a car audio shop that deals with DEI (Directed Electronics) products. The common brand names of their security products are Viper, Python, etc. I believe they have a window module that will allow an "express up/down" functionality.
Wish I knew more about it, but hopefully it points you in the right direction.
I'd make a kit for you if i had a vert nearby to use for an example =\ but like someonealready said, use a tpdt switch ifyou can find one, and connect each window to it own pole and it should be fine
Not sure what the switch looks like to drop the top, but you should be able wire a relay to the window down circuit to the drop top switch. When you hit the top down switch, windows go down also.
You can get just the window module put in without the alarm. The part # is 530t and 1 module will make 2 windows one touch up and down. If you do all for windows you will need 2 modules obviosly.