Unfortunatly there is no magic easy way to do this. It takes practice and patients.
This link has a lot of info in it and some solutions.
http://forum.thegamecreators.com/?m=forum_view&t=186489&b=24
There are some issues that can arise with custom characters if you dont use the standard biped (bones, skeleton) from FPSC. Characters could wobble about when you get close to them.
It is trial and error till you find a work flow that is good for you.
Hope this can help out some. You can also do a search for characters in the search box at the bottom of the forum pages and see what else comes up for the other 3d programs that people use.
Sometimes you might have to use a combination of programs to get your task done.