Skid angle refers to kick-up/anti-squat/pro-squat, the angle of the front or rear arms. The number put into that term on the setup sheet refers either to the angle of the arm or the number of spacers added. More kick-up gives the car less steering into a corner and more coming out. This is recommended for high bite, such as carpet because the car comes with the aggressive 4 degree hub carrier. It also helps on bumpy tracks. Caster and kick-up are not the same thing, but they work in a similar way and effect each other. I almost always run. Puting spacers under the front and rear mounts of either arm will raise that arm up on the inside, changing the roll center. I believe this gives the car more roll/traction on that arm.
On the list of new parts, the coolest thing has got to be the 0.5 degree toe-in rear uprights. Now, with these, instead of 1, 2 or 3 degrees of toe, we can use 1, 1.5, 2, 2.5, 3, and 3.5 degrees. With the 1 degree toe uprights, now the toe can go to 4! (not sure if 4 is usable
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