agilent ads s2p file

I can do one of two things, I think.

I did some simulations of transmission lines of different lengths in Sonnet. I then exported the .s2p files in Touchstone format.

Can I import those .s2p files into Agilent ADS and run some unit step or something to see the skew? If yes then how do I set that up? I'm new with ADS. Frequency range is 1-10 GHz.

OR!

Can I just do it by hand?

The signals go down copper transmission lines (striplines) and the dielectric material has a dielectric constant (Dk) of 3.2.

Is it just the material with a Dk of 3.2 that I does most of the skewing?
Meaning is it a basic had calculation of 1/sqrt(3.2) to find the velocity factor down the material? Then I can get the time it takes to get down the material by just using the speed of light times the velocity factor and then dividing that by the distance, correct?

Is it that easy?

Hand calculations for long line could result inaccurate. but it is easy.
I suggest to use ADS.

Connect a pulse generator with the desired frequency to excite at one port and the other port terminate.
see the timing and calculate the skew.