@Calleja: Check the filenames of your images, if they haven't been changed to N_X (Where N is a 5-digit number, and X the usual filename), then you messed up the 'random' file

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It'll only be randomized during a full boot (or after an update) though, *NOT* when doing a framework restart (ie. the 'reboot' file), that'll just reset the list to the beginning.