CB Gallery does work. It just expands smaller images to fit the modal window. This really shouldn't be an issue for a gallery as images uploaded to a gallery are typically taken with a phone or camera and are going to be larger than a browser window so they won't expand, but will have to shrink. There is also a link directly in the modal window to view the original image unscaled.
I'll look into fixing this in a smaller bug fix release after I've got CB Activity 3.0.0 RC2 done for release this week.
If this isn't sufficient for you then please see our stisfaction policy below if you feel you still want a refund.
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