DXMCI works great for me, what problems are you having?
I've tried it a couple different ways, but they still leave plenty of possible problems open; I've got it running but with no sound or video in sequence (have to hit escape to skip to the first FMV-choice, which I can hear Blair say, but I only have a black screen), and then it skips to the faux-fight with Maniac before it runs at a crawl--this is, however, on a fully modern Athlon 64, 2GB, WinXP system with only Win95 compatibility enabled, no DosBox or anything.
On a contemporary system, an Intel 200Mhz Pentium, it has trouble reading a file (can't remember what it is right now, I'll see if I can pull it up in a day or two again) and won't load...I've tried both double-sided DVD copies I've got, and I think that one may be too scratched, but I'm getting the same errors with both.
Ugh. It's been quite a while since I've tried to get it to run, but I'll think I'll take a concerted crack at it in the soon-time.
Alright, I've monkeyed around a little more with the game, and it seems that the sticking point is that on *both* of my copies of WC4 (both double-sided DVDs) it gives me the "Error Rendering file! (0x80030200)" message on both my new system and my main WinXP system, even after both are set up and patched properly. It then gives me the same "Error loading video!" error each time, and then tells me a video file which it gives the correct path to doesn't exist; ie "Missing movie: d:\vob\sc_8000a.vob".
Also, the screens where you choose where you move on the ship work, but move very, very slowly, including moving the cursor--and, of course, the transitions result in the error sequence. I get the exact same problems from both of my DVD copies.
I doubt that both of my DVD copies are bad, can you just see me missing something obvious?