It would be better to extrude the text in Photoshop rather than use Xara3D. Simple to do and you'll have more control. Xara is pretty poo for anything other than web graphics, even then it blows. Your marquee "cogs" work really well due to the "planes" effect that the composition has. Sticking text with incorrect lighting, blending, etc; (Xara's specialty!!) wont do you any favours.
Xara is definitely no Maya, but I find that when I need some simple text work and I know what I want, it works pretty well. Usually for me, Xara is a middle man between a photoshop/illustrator concept I've already done and an Illustrator trace that I will end up doing. For example, I used it for my Pixel Assault logo to get the dynamic 3D extrude, then the next step is tracing the whole final product in Illustrator for a sizeable vector.
It's an Ok little tool, I think
EDIT: Oh yeah... AWESOME WORK. I do agree that the text on the marquee needs to stand out more, but I wouldn't use any shadowing to get it done.. Maybe some thicker outlines?
Those gears are really something else, but what really brings it all together is your EXCELLENT use of color...
On second thought... maybe a slight black large "glow" around the text might help to make them stand out without adding any new fluff. Just a large black area that starts at about 20% opacity and goes out to 0%. Something that only leads the eyes to think the text is standing out more without taking away from the awesome background