I have a MaC. SK8 works differently than earlier versions with that push/pull tool and I had to make some re-adjustments in how I use it.
Once you have double clicked on the component, it will likely be completely highlighted. That is, all the faces will be highlighted. The push pull tool won't work. What you have to do is click on the face you want to push or pull so that it is the only face highlighted. Then you should be able to push and pull. If you hit the option button at the same time, a '+' mark will appear and that allows for a different type of extrusion.
