well bro so take a look, only way to open thi file is with UTPT, but before you need decrypt this file with l2encec, copy l2encdec in your system folder and do it, execute CMD.EXE for symbol system, with command cd you open folder, so search folder where have l2encdec with lineageeffect.u and do it, l2endec -d lineageeffect.u when you do it a file created in your system named dec-lineageeffect.u so now you can open UTPT and opend this file without problems anyway hope help you good luck here I make a screen :).
Here you have a link for download some tool don't have
[share]All you need for Customize Textures [All Chronicles]