Bugs or eccentricities -- you be the judge.
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The first one is simple to describe. If you enter Actionscript manually (expert mode), then be careful about extra spaces if you end up deleting all the script. What I mean is, I used to have something like
some_variable = "whatever";
gotoAndPlay ("SOMEFRAME");
Now in this example, say I delete both lines of script, but leave the line returns untouched. Easy to do, since it certainly looks as if I've cleaned out all the script. But when I click on another frame, I see there's still a little 'a' inside the frame I just left -- in other words, Flash sees the line return and assumes there's actionscript lurking within.
Normally, this shouldn't be a problem. But it was for me. Movie A loaded movie B into a clip; movie B happened to have some of this phantom actionscript on its first frame; when testing the movie (either within Flash or through a browser), a library symbol that did not exist on the stage of either movie would inexplicably appear when movie B was loaded.
Weird, eh? I tried enough combinations of things to conclude that the phantom actionscript was at fault. I deleted it and everything worked. Absolutely bizarre. So be aware these things can happen.
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The second problem is something too complicated to describe, so instead I'll just give you the advice. Essentially, Flash appears to have some type of 'complexity limit' per layer. I had multiple instances of the same complex movie clip together on the same layer, and very, very bizarre things started happening. After 90 minutes of weeping and gnashing of teeth, I solved the problem by putting each instance on its own layer.
I know what you're thinking -- I must have missed some other little thing. But I didn't. I checked everything and I mean everything. Three times. There was no reason Flash shouldn't have worked with everything on the same layer, and equally no reason that using multiple layers should've made any difference. But that's the way it was.
So -- in summation -- in my opinion, if you watch out for phantom actionscript leftovers, and don't put multiple instances of complex movie clips on the same layer, you just might save yourself some future tears.
A small favour:
Please post a reply -- anything (even just a smiley) -- so that this thread won't get buried thirty minutes after it's born. Maybe it can even garner a "hot" icon, ensuring that plenty of Flashers will see it. Thanks.
And certainly, post your own "Stories from the Beyond" so we can all read the warnings.