1. YES. I've done it using port 2 (since that's a line port)!
2. I've also recorded from the USB port on the SC X2 directly into the computer to Studio One. That requires configuring the SCX2 in the OS audio device list as a Recording device. Can't remember if I've also used the SC X2 as the Playback device. I did it before I purchased an Audiobox 96 and had no other way to record my guitar..
Using the Audiobox 96 is a simpler solution but if you have some friends over, it's always good to know you have another port available by going directly into your computer. ;<))
Both of the above were done using Windows 8.1. I've not tried it on a Mac yet, but I have an old Mac laptop coming my way, so I'll have to give that a try.