You can try the offy=(some hieght) in the characters FPE file in the top section.
But I am suspecting that the character was rigged with its waste at ground level instead of the feet in the 3d application that it was made in. This tends to present the problem you are seeing.
Try the offy thing first. Make sure you clear the dbo and bin file for that character and reset it in the map editor.
If that still dont work then you will have to set the character mesh with its feet at the 0,0,0 position in your 3d program, rerig it and re animate it , then export it and see if that works.
The speed issue could be the difference in frames per second that the model was exported out at. You can increase the speed setting in the fpe file for that character to maybe speed=133 or more to suit your needs.