Those are very nice designs... but since I'm a pain in the butt (i.e., I want you to succeed here, despite the challenges) I have some questions:
1. Is this thing, or the "polished" versions... UV-mapped and skinned? I don't see any skinned versions, and spacecraft without skins won't render in the FL engine. And, sad to say.. those of us who're any good at skinning (not me, obviously... my ship skins are pretty bad) are all busy working on the "leet" mods, and won't have time to help you out.
2. What's the polycount? From your wireframes, I'd guess that each one of the "rear thrusters" was over 100 tris apiece, let alone other areas where you have more complex curvature than you really need, such as the cockpit. Try to get the total model polycount below 3000 if at all possible- I'm guessing here, but it looks like it's between 6-8000 tris right now... waaaay too high for best performance.
If you can get it split up into UV-Mapped Groups with proper skins at the target polycount, you can email me for help getting beyond that point. Your model shows that you've got talent- getting from "talent" to "in FL" involves several more steps, though, and you'll be happier in the long run if you learn how to do it yourself. At any rate... best of luck, and hope you finish the ship- it's a very nice Anime design and true to the reference materials