my decompiler in q3map2, and when i try to use it , it gives me a message "Error
Usage:C:\ Program Files\ Lucasarts\ Star wars jedi knight academy\ Gamedata\ q2map2_2.5.13_win32_x86\ q2map2.exe [general options] [options] mapfile "
how do i fix this ? 
In your batch file, use fully qualified paths with unix style forward slashes and put each path in quotes, for example:
"c:/program files/lucasarts/jedi academy/gamedata/base/maps/foo.bsp"
Also specify the game and format:
q3map2.exe -game ja -convert -format map
If you have any more troubles, post your full batch/script.
Use one of the many front end programs such as Q3Map2 Toolz or Q3Map2Build. Search Google for “Q3Map2 front end” and you will find several.
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