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The skin pages are loaded with a cross-directory include() from the skin loader. Your skin should never assume to know its relative path on the server. It should rather construct all paths with $skinObject->findResourceUrl("IMAGES") (or "CSS" or "EXTERNAL" or "BASE") if you want to reference a image resource from the "global" stock of images (our stock is contained in the web/resources/ directory) , and a $skinObject->findResourceUrl("IMAGES", true) if you want an image that is only relevant for and confined in your skins/YOURSKIN/ directory. Your directory structure MUST mimick the one in web/resources/ for things to work.
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