yes i've had the same thing happen. i've also had some keyboard themes in the store not come up at all it just applies the default keyboard... i always download the trial before buying because this has been an issue for me as well.
I would recommending checking to make sure the theme is compatible with the current Android version you are running on your device.
I don't see a way to check if the theme is the updated version. It just says this if the OS is updated the updated version of the theme can be gotten through purchased items and not all produced updated items.
What has me baffled is that even on the themes that just came out it's the same thing with things not matching. The keyboards are all a flat design no matter what the image shows.