LVL Extractor is a command-line utility. So, in order to use it, you must run a command-prompt and "point" to the path containing the *.LVL file to extract.
Here is some steps which might help you :



Open the Start Menu, then go in "All programs > Accessories > Command prompt" ;

In the MS-DOS window which should appear, enter :
Code:
cd [The path where the *.LVL file you want to extract is present]

(For sample, type "cd C:\My LVL files" if you want to get the content of LVL files which are located in "C:\My LVL files".)

After that, be sure LVL Extractor ("extract.exe") has been installed in the directory which has the LeVeL files whose content must be extracted ; Still in the MS-DOS prompt, type :
Code:
extract [The name of the *.LVL file of your choice]


Wait the end of the extraction process. Next, browse till the directory chosen in the command prompt, and you'll find a new folder named "[The name of the extracted *.LVL file]". Open it, then go in the "tex" sub-folder : It owns all textures which were compressed into the *.LVL file you chose to extract.