Last night I finally picked up my copy of PMDG 737NG (after much debate on whether or not I will get a slide show on my computer, it actually turned out great!!).  Anyways, it was my day off work today, and obviously, I spent countless hours fiddling around with the lovely 37.  There are a few questions I was wondering if any of you could answer though:

1.) Theres two autopilot cmd buttons, what is the difference between them?  And also, what are the CWS buttons below them and what do they do?

2.) After I land my aircraft at any destined airport.  Whenever I advance my throttle above say... 5-10%, I get this annoying horn.  What does it mean?  I only get it when im landed and taxiing, not during my departure phases.

3.) In the FMC, I set path descent, and when I reach my point of descent, the FMC pops back with path descent not available.  Can someone fill me in on the procedures and purposes of both path descent and spd descent?

4.) As I fly multiplayer ATC a lot, there are often times when the controller would tell me to fly direct to an intersection and break off my flight plan.  If that is the case, would I go into my FMC and delete my waypoints and re-enter an intersection or is there a faster way of doing this?

Thanks for the help

The 737 has 2 autopilots: A and B anyone of them can work the aircraft at any time, and they are driven by 2 independent FCC's (Flight control computer)

CWS is short for Control Wheel Steering, and it can hold a specific bank (CWS R) or pitch angle (CWS P) for you, kinda like the charactristics of the airbus FBW. So if you are banking 10 degrees and press CWS the aircraft will keep the bank angle no matter what.

The warning horn is warning that the speedbrakes is probably extended (autospoilers extended during landing, and you still havent retracted them). Also, since the horn is a tako-off warning, it also warns that you don't have Take-off flaps selected. So why this warnings then? In reality, the 737 needs very little thrust to taxi and the horn wont go off with such a low thrust lever movement.

If you have the intersection in your flightplan, just copy it to the scratchpad and make it the next leg, then execute it. Now the FMC will give you desired intercept angle, aswell as Abeam waypoints.

Regarding the descent, this is the stage where most beginners have problems. The messae you're getting means simply: The descent path is too steep and the aircraft cant fly it or else it will overspeed. A little hint is to use the DES NOW a few mins before  T/D, this will get you a nice 1000ft/min descent until it intercepts the original path. If that doesn't work, use the speedbrake or modify the constraints

Thanks for the help guys!