The NX kits are pretty good. I have had good experience with their solenoids over the years. And the nice thing is you can send in your NX solenoids to NX or some dealers and they will inspect the solenoids for you at no charge. Some other N20 companies do this as well, but I have had the best solenoid reliability with NX.
The NX kit will come with a microswitch, but you will likely have to fab your own microswitch bracket to get the microswitch to engage just right with the bell crank(throttle blade).
On a 5 speed the window switch is up to you. If you are an experienced driver you won't need one because you can completely control the RPM you shift. If you get serious about going to the track and run some sticky tires and are launching off the juice in first, then a window switch will come in handy. A window switch becomes more important on an auto because the PCM has control over the shifts. I'd recommend getting yourself a quality aftermarket tach because the factory tach can be significantly off escpecially in the upper RPM's.
The nitrous line being longer than the fuel line is another internet myth. On a wet kit the N20 lines and fuel lines coming off the solenoids can be the exact same length going to the nozzle. You can hold the nozzle in your hand and hit the WOT switch and the N20 and fuel spray at the same time.
If you need any wiring help, there have been some posted in this forum, and NX has some on their site as well.