When using Screens (forms/slides) in Flash MX 2004 pro, is it possible to load
a movieclip ABOVE every screen. For example, I want to have a pop-up
navigation on every page of my presentation, that pops above the screen's
content, not below it.

The only way I know of now is to just have the nav on EVERY screen, but that
seems tedious if I need to update it, plus the built-in transitions will apply
to the navigation also, not just the screen body. I'd rather have the nav MC
pulled dynamically and placed ABOVE every screen, or have some kind of master
screen, that is above everything else.

The presentation screen is above all other screens. It is the master screen.
You can load content/nave/whatever into that one.

But all the child screen's content lies ABOVE the presentation screen content. I want to add content that lies ABOVE ALL the child screen content.

You and I are not using the same Flash 2004 pro then.

[quoted text, click to view]
content. I want to add content that lies ABOVE ALL the child screen
content.
[quoted text, click to view]

I just tried this. Flash MX 2004 Pro:

1) Open new Flash Slide Presentation
2) On presentation , draw a red square
3) On slide 1, draw a blue square
4) Test movie

Result: The child slide (slide1) shows ON TOP of the presentation slide.

Is there something I'm not seeing here?

I want to display a slide on top of all the other child slides.

SWEET! Thanks. I'll give that a shot.

Sorry. You are right and I am wrong. Make your red square a movie clip named
"red_square". In the timeline of the presentation slide place this script

red_square.swapDepths(this.getNextHighestDepth());

If you do this with your navigation, it will also be above all else.

No problem. Sorry for the confusion. I generally create all movie clips
dynamically rather than on the stage so it treats the depths differently.
Dynamically created clips will be on top by default. It is authored clips
that get negative depths. That is unfortunate in the slide format because,
for me anyway, it seems to violate the visual structure.

I just had a quick look and all child slides of the presentation slide get
negative depths assigned to them (makes sense really) so if you use
getNextHighestDepth, it will assign that a depth of zero as that is the next
highest "valid" depth. So, instead of swapDepths(this.getNextHighestDepth())
you could also use swapDepths(0) and achieve the same result. What is in the
child slides themselves or their children is unimportant since they have
their own timelines.