Right click your Last Moon icon, and then click Open File Location. It will bring you to your LM folder, where you will see something like this:

open the update.log as circled in the image. If you get a pop up, open it with Notebook/pad (I forget the real name for it, but it's Window's default text editor.) Select all of the text inside (Ctrl+A) and then copy(Ctrl+C) its contents, and paste(Ctrl+V) it into a reply here!