You can either rename the l2.bin to l2.exe or download the one from fyyre, make sure yu download and copy the right one from there, another thing if you patvh the system folder with l2encdec make sure of use patcher -f ,in order to force the patcher yo jump errors, otherwise it will stop in the middle while patching...
If the walker doesnt attack try tomodify the policy saeting using either long ranfe or melee attacks always, that wayyoull forcea skill or attack at close/mid range.