Hi
I downloaded both FLAs. And yes, testing graphics.fla brings on a SWF with expected speed, and testing movie_clips.fla brings on a very sloooooowww SWF. So far as you described your problem. I had no crash, though.
Then I saved movie_clips.fla under a different file name and reduced the number of characters from seven to one. I just wanted to know by which number the problem starts or increases. Hence successively I increased always by one and tested. Now I have eight Hick characters on stage and the speed's still fine. And Advanced Layers are on.
So I can't really tell why my file is working, apart from that I use Animate 19.0 Build 326. (I can't use the latest release because there's a bug with web fonts in HTML5 Canvas documents). In your file one character instance was set to Button in the Property panel, though I don't think that was the cause.
Perhaps you try out my file with eight characters and good speed. How it fares on your machines.
Dropbox - movie_clips_xp.zip
Klaus