If you update the slimbox script in MaxiGallery to the latest one, it might fix your problems.
But if you want to get rid of those completely, do a custom galleryPictureTpl that renders the html like the slimbox wants (eg. copy the default template and remove everything but slimbox parts.. note: also remove the condition syntaxes). Then call maxigallery without display and embedtype parameters and use your custom galleryPictureTpl.
This way maxigallery formats the html like slimbox wants, but does not add the slibox resource files on to the page automatically, so you need to add those manually.
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