How to load different modules in moduleLoader - some with other without unload?

Question

Ok so I've read a lot about modules and I decided to build a site where I have a button bar menu and a single moduleLoader, where all of my pages are separate modules. Some of the modules will be preloaded with moduleManager technique so they will be in memory and should pop up instantly and others should be unloaded since they will be used rarely. Imagine you have 50 pages, 45 of them use the same 3 modules and the rest 5 use 5 other modules.
So I need 2 things:
1) those 3 modules preloaded (loaded into memory) and then used - this is not a problem. In the change handler of the button bar I just set the url of the moduleLoader=""; and right after that line I put moduleLoader.url = "module1.swf" for example. This way the ready event fires everytime I change the selected button of the buttonBar and since the module is loaded into memory it changes immediately, which is great.
2) I need the rest 5 modules that are not preloaded, to be loaded by the moduleLoader and when the user clicks on another button, the module to be unloaded and the new module for the new selected button to be loaded on it's place. So here unloading of the old module and loading of the new one should happen with 1 user interaction - clicking a button. How do I do that?
I am asking this because I found out that there is some difference when the module has been preloaded or not which changes the way it unloads. Also in certain cases if a module has been unloaded once and loaded again it stops shooting the unload event by only changing the moduleLoader.url and then you have to specifically call moduleLoader.unloadModule() function to get it called.
And all of this brought me to the idea that maybe the only way to make this work for case 2 is having moduleLoader.unloadModule(); and on the next line after it moduleLoader.url = "newModuleUrlHere";
But then I bumped into a problem with flickering in my buttonBar selected button transition which I describe and give online example of here:
http://forums.adobe.com/thread/760347?tstart=0
So is there any technique of combining preloaded modules which should not be unloaded + the ones who need to be loaded and unloaded and all of this to be working with just one moduleLoader instance?
I really didn't expect to have so much trouble with modules... If no one can suggest me a working example I will post each case I described here to help me get resolution to this cause I can't get on with my project and it's very important.
Thanks in advance!

Answer 1

Hi thanks for the reply here too
I agree it totally makes sense if I do not unload modules to load them in the same application domain and not as a child. This way I wouldn't have to worry about the singletons I could have forgotten to initialize in the main application If my logic is correct. But still is it wrong to leave them in a child ApplicationDomain since I will still have modules I will need to unload and I would still have to be careful about the singleton managers?
Note: have in mind I am trying to separate the module's from the main application, so the application won't use any classes defined in the modules since it won't be aware of what's in what module.
Yes, I do have a buttonBar buttons which map to module urls.
Ok I will try to setup my questions in a few very simple example applications, it would be easier for you to understand what's confusing me.
http://filip.nedyalkov.net/moduleLoaderTesting2/ - view source enabled - look at testing3.mxml
In the button bar change handler I have:
moduleURL = buttonBar.
selectedItem.url;moduleLoader.url = moduleURL;
and I listen to the moduleLoader unload event.
On the Unload Current Module Button I have: moduleLoader.unloadModule();
Ok what is confusing me is this: When I start switching between module1 and module2 do they automatically get unloaded because I recall reading that changing the moduleLoader.url property doesn't unload the module just releases it? Also I'm getting the unload event shoot very strange because if I am on module1 and then click on module2 it doesn't shoot that module1 was unloaded, it doesn't do anything. As soon as I click back on module1 then it shoot unloaded (you can see that in my example in the text area).
Another strange thing is that while doing this, everytime you click on module1 or module2 they get transferred over the network I can see that in mozilla firebug. Now if I am on module1 and click the Unload Current Module button the module really gets unloaded and then the unload event is correct and shoot when it's supposed to shoot. Now if you click on module2 and then come back to module1 it will get loaded again, but now it will be put in memory, it won't shoot unload event any more and it won't get transferred over the network when I switch the modules? Why is that ? All I did was unloading the module once and it changes everything.
So I hope you undertstand this cause I have no idea is this supposed to work this way? Would you be so kind to explain me this behaviour ?
Thanks!