Blender

[Erik]

Can I use the blender3d program to make models and animations and import them into CS?

[intruder_xo]

Hello Erik,

Yes you can, but you need to export them into Cal3d format, they have some plugin available to do that.  Also if you take a look at the community site you will see tutorial on how to make them.

[morgul]

Actually, I would venture to say that blender is the best supported modeling program for CS.

--Chris

[dingobloo]

No venturing required, blender IS the best supported modeller for CS.
The feature list of blender2crystal,physics,shader,entity scripting and physics support is unparralleled by any CS exporter (and evensome proprietary game engine editors) in an almost embarrassing fashion.

[deckerego]

Along the same lines, blender2crystal is currently allowing you to export spr3d libraries... so you can do animated genmeshes without the cal3d plugin.