Ah, you're talking about that bug that causes the game to crash when it tries to load the opening video. I thought you just meant you could play the game, but couldn't see the OP.
Well, that problem is a bit more complicated. It has to do with your video setup. Your codecs and filters and such. Most likely your vfw filter chain has been broken, because some of the codec packs you have installed on your system have been messing with it when they really shouldn't be. How it works is a little complicated, but, basically, a vfw filter chain determines what Windows passes stuff off to for decoding first, and like anything else, it must have a default value. You don't mention what operating system you are using (always include details on your system when posting errors, as per the guidelines posted on the first page of this error reporting thread), and I'm not sure how it is with Windows XP, but Windows 7 at least has a set of native filters to handle most stuff, using its own codecs for decoding several audio and video formats, and so using third party DirectShow filters instead of the native filters is not possible without making difficult changes to the Windows Registry. The problem is that some programs and players, which are able to use third party filters just fine on their own, try to very aggressively replace Windows' native filter set with their own, basically telling Windows "Let the program decide for itself which filterset to use!". This can sometimes break games, because the game is expecting the Windows filter set to handle the video/audio, and handle it in a certain way. This way the game doesn't have to actually think about it. If Windows tells a program to choose a filterset, but the program was never DESIGNED to choose a filterset to begin with, then bad things happen. LAV for example still has some issues where in certain situations it can crash when it is called by programs as the filterset.
As such, one last resort solution is to simply delete the opening video (or move it to somewhere outside of the game folder, so you can watch it manually outside of the game, using the media player of your choice). Filters can't mess up when they can't play. :-) You only said you've tried "replacing" the video, so I'm gonna assume you haven't tried deleting it. Then again, if you delete it, then you won't be able to see it when playing the game. Nothing huge of course, since you can play it manually with the player of your choice outside of the game, but there is a possible "proper" solution, if you're a little adventurous. You can download this tool:
http://www.codecguide.com/windows7_preferred_filter_tweaker.htm , and then open up the prefered decoders, and make sure everything is set to either "microsoft" or "merit". Setting it to "microsoft" would probably be the best option to try out first, and then if that doesn't work, you can try "merit", though it's possible that that one may not work either. The idea is that setting the filterset to Windows, if it isn't set to it already, may fix the problem because now the game should say "Okay Windows, go handle your video thingy". It may not work, but it's worth a shot if you want, and if all else fails, you can always delete the OP video. Bear in mind though, that making these changes will affect everything else that uses your codecs as well, so use the program with caution. If it breaks everything, then you need to set things back to how they were before you made the changes.
A long response I know, and it may not have been as helpful as you had hoped for, but I hope it was of some use at least. :-)