Well, before I answer Your question. This shourld not be under models and media, wourld fit better under Chat. (There are more answers there) Ok, first I want to tell You the ugly truth, that it is very few model software that export to FPSC, the only ones I know is Fragmotion and 3dsmax.. Im talking about animation sence that was Your question. When it comes to export of static objects many more are capable to export working .X files.. Try to export in another format, like FBX from blender to fragmotion, and then it will work! Otherwise try formats until You find a format that works in fragmotion...
Good Luck!