Flash, properly implemented, is GREAT. -- When used for annoying, crappy advertisements, sucks.
The scripting language isn't terribly hard to learn (then again, I'm a software engineer, so maybe my idea of "easy" is different than mere mortals
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I'm not familiar with that plugin, but based on your description of what you want to do, and what that plugin claims to be able to do, I'd say it wouldn't be all that difficult.
I don't have any examples as they were all done for work ("hey, its sort of like programming, have the software engineer do it!"), and as a result are not exactly mine to show off. I personally do not have a copy of Flash because I don't have any projects in progress or on the "someday" list that would make it worth it.
Posting flash files is pretty easy -- upload them like you would any other item to your web host. Embedding them in HTML is also pretty easy, and if you go for Studio 8 (see below) dreamweaver makes it effortless.
If you're going to shell out the $699 for Flash 8, give some thought to buying Studio 8; Dreamweaver is a very nice web development program, Fireworks is useful for easily creating buttons for your webpage (I know, you can do it with Photoshop CS2 as well, but depending on what you're doing, it can be easier or quicker, if not better).
Plan on spending some time reading books and internet how-to's and just playing around with it. Like anything, it does have its own learning curve, and you really can't short-cut it too much.