There no need for me to jump in here. But if I understand all this correctly…

Mitch stated that he wanted to broadcast a live 24 hour video stream, using “YouCam”. I don’t think too many folks completely picked up on the YouCam part.

Now I may be way wrong here, but what I envision Mitch wanting to do, is have a web cam fixed on “something”, perhaps a box full of newborn puppies. Then people can tune in to this streaming feed of the new puppies, 24 hours a day, to see what the puppies are up to at any given moment.
But perhaps let’s say that Mitch is also a puppy breeder, and also has an online pet supply store. So Mitch would like his two company logos to alternately display in the bottom left corner of this live 24 hr streaming video.

I don’t use YouCam, but I am aware that it supports Particles. Using YouCam, you can for instance be on Skype, and have a Particle effect of stars or hearts swirling around the screen as you are chating with someone.
There are also particles that will appear as if you are wearing a cartoon hat, and as you move your head, this layered cartoon hat Particle, will follow the top of your head.
So perhaps Mitch is thinking that if he could adapt or modify or replace these swirling stars, or cartoon hats, with his two logos that remain in a static position, and, alternate on and off, then… mission accomplished.

How does PowerDirector figure into all this?

Well, because PD9 is where the Particle Designer is. And where you can modify and create your own custom Particles
These Particles are .dzp files, which are supported by YouCam (GIF files are not), just like all the other available .dzp Particles available for download on the DirectorZone, that are supported by YouCam.
So, if Mitch can modify a Particle effect into being his two logos instead of two cartoon hats (as he described above), he will now have a live webcam feed, running 24 hrs a day, with two alternating images (particles), also displaying 24 hrs a day. And it will all be self contained within his YouCam upload stream.

But it’s modifying the particles to behave in Mitch’s intended manner, that is the sticking point.
I’ve played with trying to modify a particle to Mitch’s specifications, and am getting close. But I am not able to get it exactly to what he’s described, because of a fade in/out issue.
As Mitch mentioned, there are some seemingly inconsistent behaviors found, when modifying in Particle Designer using the adjustment tools. And this became apparent during beta testing a year ago.

If I am way off in my perception of what you are trying to accomplish Mitch, and this is not at all along the lines of what you have in mind, then please let me know and I’ll delete my drivel here.

Click here PDtoots for a collection of PowerDirector Tutorials and Tips

Cranston has it exactly.

Here's a 24-hour camera that runs forever:

http://www.ustream.tv/channel/friends-of-felines-rescue-center-24-7-kitty-cam

And then here are graphic effects for YouCam, made with PowerDirector:

http://directorzone.cyberlink.com/youcam/#PFX-downloadCount-mp

Many run forever on a loop. Like, forever.

I just want effects that alternate between two images. I didn't want to explain what the images were of or why because I wanted to keep the question simple. But the video will be of cats and kittens playing at an animal shelter, and I'm going to have news-like graphics on top. I already have a "news ticker", a logo, a headline, and a "Live" icon. But there's a small subhead below the headline that I want to alternate between the name of the shelter and its location, because it's too much info to fit at the same time, and starts to obscure too much video. It's not absolutely critical, and I can ditch the idea if I have to, but it seems like there must be a solution. There are plenty of other effects that have multiple particles emitting forever, but once you try to have them alternating, they seem to want to synchronize. It's very odd.

And don't bother with text in PowerDirector, it can't be used in YouCam. It has to be images of text treated as particles. (Which is a pain when it comes to the crawl, because if particles are, say, five times as wide as the screen, and you set them to 500 so that they are displayed that way, you get an extremely blurry image. So you have to piece together five images that are the width or less of the screen and perfectly time their starts to look seamless. And that successfully runs forever because it's not alternating and there's no need for an EmitInterval -- the particles just continue unseen off-screen until they repeat.)

Now I fear I've complicated people's thoughts about this, but it's still as simple as before: two particles alternating. How do I keep them from synchronizing?

I have nothing to add except this is getting very interesting.
Too bad I don't have the FULL version of Youcam so I could get involved. HP Envy Phoenix/4thGen i7-4770(4@3.4GHz~turbo>3.9)
Nvidia GTX 960(4GB)/16GB DDR3/
Canon Vixia HV30/HF-M40/HF-M41/HF-G20/Olympus E-PL5.
Tape capture using 6 VCR, TBC-1000, Elite BVP4+, Sony D8 camcorder with TBC.
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