Just thought I'd post up how I bring my config to lan seeing as there always seems to be issues and this has worked for me every time.
Open Steam Library -> Right Click on Counter Strike: Global Offensive -> Properties.
Open Local Files tab.
Choose Browse Local Files.
Open 'csgo' folder .
Copy 'cfg' folder to where you want to back up the files.
Now go to Steam folder -> Open 'userdata'.
There might be a few other folders named with Steam ID there if you are using multiple Steam accounts. If you use one account only, there will be only one folder. You can find ID for your main account here. (It is the Steam 3 ID). Then open the folder.
Copy '730' folder to USB