A question for all those in the know: I wanted to play a map, but when I launch the game (a licensed copy) on Vista 64, it freezes my computer, to the point where I have to restart it. The editor launches normally. Has anyone encountered this, and how can I fix it? The first three parts of the game work normally, but this one is a complete letdown.

I don't know, BUT! Try setting compatibility to WinXP SP2, and/or 256 colors. These methods often help me when I have conflicts with programs. I don't have any problems with the fourth game on Vista (though it's under x86).
I've also heard that older versions of StarForce can "overload" the system on Vista, even causing it to freeze. It's recommended to install a special patch for StarForce. Search for it on Yandex; I found it before.

Added 20 minutes later
Here are the StarForce drivers for Vista.