K, I *just* finished "fixing" my HotU install of FS2, and I have the following advice:
Don't. Just don't.
Make a folder for the install, download the latest FSOpenInstaller, point it to your intended directory, and walk away. It'll take a while, but it's still faster than trying to "fix" the HotU version. The cutscenes aren't the problem. Since that version just plain doesn't have em, the FSOpen install will replace them. The real problem is all the sound files, specifically for radio chatter and mission briefings. They're all there.... as blank files that are 1kb a piece. I tried a repair install twice with no success, manually removed all the files and replaced the ini, nothing. When I got FSOpen fully loaded I tried to use the autoupdater to replace the files, no dice.
Don't screw around with the HotU version unless you just need something to tide you over while a cleaner install is downloading. There are a number of options linked on this forum, and they're all better than the HotU package.