Images smaller than container size makes the zoom image go crazy

the temporary solution is to use image style to enlarge your image if it is too small..

Subscribing

Ok I fiddled around with this a little. Actually maxchock's workaround works but in case other people need more precise instructions (as I did), read on.

Basically on the Manage Display for the structure which has Cloud Zoom enabled on an Image you need to set the "Zoom area image style" to an Image Style that is always bigger than the "Slide image style" option directly above it.

For me this involved creating a new Image Style called "xtra_large" that scaled all images to be significantly larger than the Image Style selected for "Slide image style" (eg 1.5x or 2x across all dimensions, depending on the quality of your original images, how much you want to zoom by, etc), and allow upscaling.

So for example if you are using Image Style "product_full" in Drupal Kickstarter (as per OP) for the "Slide image style", it creates images 400x550, so you might want your Image Style "xtra_large" to have dimensions 800x1100 (doesn't necessarily have to be same proportions, in fact thinking about it now it possibly makes more sense to have the dimensions square).

Allowing upscaling can have some unintended consequences but for a quick fix that works reasonably well when you have base image sizes that vary considerably this was the best configuration I found.