If you've experienced problems running Christopher Subagio's HDRdomeLight script after applying Max's 4.2 patch then check the version of your core.dll file (in your root Max directory, click with the right mouse button over the file, select properties -> version), which should end with a .86. If this is not the case then download the latest patch (again) from Discreet's website and apply it to your Max directory.

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