I did a search. As for the Cutscenes in-game being similar to the WCM Kilrathi Craft...clearly you do not have enough experiance playing Starlancer. Those are quite obviously not Kilrathi craft.
in fact, while there are certain design similarities, you have to consider that when one is dealing with large space dwelling ships of death, there are only so many original designs, and a number of features are going to be the same on all of them.
The only ship in the game that looks remarkably like any Kilrathi ship is the Shroud. This is also the ship pasted on the cover I believe, why I'm not sure. Personally, that sort of light fighter is a piece of crap. I like something heavier, like the Pheonix or the Reaper. The only advantage it has is cloak, and you only really get to use that effectively on one mission.
Other then that, I think the ships designs for Starlancer are great. Especially the Carriers. Some of them, like the Endevor, are on crack. But the Coalition carriers especially, are nice. The Reliant is ugly as sin. The Yamamoto looks like something from Battlestar Galactica...and well, if you've seen the Victorious I don't think I need to tell you what it looks like.
You're obviously confusing Starlancer with another game. Your post doesn't make any sense, BTW. The ships seen in cutscenes are the same ships seen in game, with the exception of that video clip (Which is obviously ripped from the WC Movie, however, since the Movie and the Game are both Chris Roberts creation I don't really have any complaints about that, it just confused the hell out of me when I saw it). So how can the ships in cutscenes be ripped from Kilrathi Ships in WCM and the ships in game not be? Maybe you just phrased your post wrong and meant to say both. I don't know.
As for it being discussed before...I did a search and read all the relevent threads I could find, and found nothing. I know that Starlancer and Wing Commander are closely related, their origins are the same, and that they are often compared to each other. But still...using footage straight from the movie and dumping it into the game like that...it's just a bit disconcerting. Especially when you consider that every other scene in the entire game is Rendered, and that's the only one that's not. And by rendered I mean animated with characters whose faces look believable and whose hands never move. It just doesn't fit.