Cinema 4D is a brilliant tool, but isn't exactly great with windows game development - especially with .x files, though there is the 'xporter' plugin that may be able to export successfully. Though I've tried loading .x files from Chinema 4D into DBP and it hasn't yet succeeded in importing them. So I doubt they'll do so well in FPSC - however I have seen users succeed.
(Models do import, however they've been texture-less and non-animated in my experience)
Cinema 4D is great for CG art, animations and is meant to work nicely with Mac games engines like Unity3D.
List of apps I've seen tried and tested that work fully with DBP that will export textures and animation (and should therefore be successful with FPSC...unless it requires some kind of specialism)
Dark Basic Pro uses the .x and .dbo file format (though .dbo's will need to be converted from .x)
Milkshape3D
3D Studio Max
Maya
Softimage|XSI
Blender
GameSpace
TrueSpace
3DCanvas Pro
Lightwave 3D (Apparently is exports really smoothly now, and is one of Cinema 4D's rivals, and is probably almost just as easy to use)
You can always mix and match, I no longer use Cinema 4D (I used the very outdated version and managed to get to use Cinema 4D 9 to test its compatibility)
So my toolset currently consists of (what I used them for in brackets):
Hexagon 2 (Modelling and organic UVMapping)
Carrara 5 pro (CGI, procedural texturing, can work directly with Hexagon)
Lithunwrap (non-organic UVMapping)
Photoshop 6 (texturing)
Milkshape3D (exporting to DBP and animation, and making sure textures are attached)
"Experience never provides its judgments with true or strict universality; but only (through induction) with assumed and comparative universality." - Immanuel Kant
