I've never seen an Illustrator Import warp like that before. Did you save your illustrator file with the Illustrator 8 format?Either way, you'll have to do a little reshaping by hand in Moho to get it the way you want.
As for bones, have you checked the Bones tutorial? It's all in there. The only real 'trick' to bones, is that it's often preferable to have the individual parts of a character on seperate vector layers, especially parts that are going to bend with one another (ie: Forearm and upper arm should be on seperate layers), because if they are one solid piece, you sometimes end up with distorted elbows/joints.
im just making a guess but it might be the skin tone isnt a clour thats moho compatible and the lines may be hard for it to decipher as you may of used different tools to mohos program but as i said before im a newbie here so its just a cheap guess
dumb people do the math, smart ones use a calculator