Vacuum system

If anybody can help, I'd sure appreciate it! My son and I just recently regasketed a 96 Plymouth Grand Voyager 3.0 L. I am giving him the car after I purchased a new Murano, which is the first NEW car I've been able to drive since he was born 20 years ago. About time... So the wife says, 'Before you give him the van with 100k mi on it, I demand that you fix that mysterious leak coming from the car that you've been ignoring for the last 30k miles.' This is because the last two cars he's bought from friends have been junkers with 100k+ miles, and he's killed both of them and then called us from two states away asking for help. So we get a gasket kit from Pep Boys, arm ourselves with a Haynes Manual, and tear into it, to replace all the gaskets down to the head gaskets. This meant replacing the timing belt, plugs, plug wires, etc. (Never having done anything remotely this intense before, mind you.) After several weekends putting it all back together, we tried to start it today and we're not getting anything for our efforts. Two things are bugging me: 1. My son kind of messed up the hose that goes from the left valve cover to the resonator, so that needs to be replaced. Could this be a reason for not starting at all? and 2. the vacuum manifold connector on top of the intake manifold has one open fitting. We can't find any leftover hoses that should be going on to this, and the Haynes manual showed two pictures of it, both of them without anything on the fitting. Is this supposed to be open? So if you're familiar with the Voyager vacuum system, please help. And I hope you like my novel I'm writing here... :) Thanks in advance for anybody who made it down to this point.

This is me again. Here's what I've done in the meantime:
1. I've checked the timing with a timing light. It shows the crank pulley exactly where it's supposed to be.
2. I've checked spark at all six cylinders. It's there.
3. I've smelled the plugs when they come out; there's fuel at the plug.
I've tried a check with a compression tester while cranking it (remember, it won't start). I'm getting about 150 psi.
On suggestion of a couple of people, I've replaced the crank sensor. Still no go. So it's got new plugs, new plug wires, new timing belt, new crank sensor, the timing checks out, I've got spark, and I've got fuel. What gives? :banghead:

Thanks for any help. Somebody please...