Will it fly: The professional engineer's perspective..... yes. Quite literally, you can make a brick ****house fly with sufficient power. Not well, but that is left to the software engineers (read: Brads) to figure out.
The only issue with a fast zeppelin is that the manifold (the baloon thingy) creates a lot of drag. You can go fast, but it'll take a lot of power. Frankly, given that the GW universe seems to have INSANELY effective aircraft-scale power sources (for flying bricks like Stormravens and Thunderhawks), I actually think that a high speed zeppelin troop transport is *feasible*.
*Why* is a good question. A comparably sized winged aircraft could move faster and carry more payload for the same powerplant. Then again, clearly the Imperium is very aesthetically oriented, and more than willing to do crazy things, so DO IT! ALL THE AWEOME!