Javascript not working

[ZiNgA BuRgA]

You still didn't post an error message.
Never mind, the issue is this:

Javascript Code

var position = 'img[i]' if(imageresizer_gd_warningposition == 1) { position = 'img[i].nextSibling'; }

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position is meant to be an object, not a string, so remove the quotes around them.

Oh, and the code is absolute shit, from a performance perspective.  You're probably better off not using it at all.