Finally finished! So much micromanaging on this one!
Skills maxed = 20 = 20,000 points
Got one skill to level 8, so thats 400 more points.
Finished 58 skill challenges, for a total multiplier of 3.9
So 20,400 x 3.9 = 79,560 total score
Can't wait to see how this score compares to my one on Ricas!