step 2 problems

What exactly does step 2 do?
"
System Checks - The installer checks your system to make sure that it will support G2."

I'm getting a complicated error message and have no idea what it means; the essence of it SEEMS to be that a file is missing and I've checked and it isn't.

So maybe the way of resolivng this is to understand what it is checking for etc, and set it up properly if its not already.