Nicholas,
This issue usually is related to the container of dotnetgallery.
Please check the following example:
In the above example, no matter how smal/big the image, the image will be in the center of the parent container.
If you check the HTML code of the above example, you will find out the following code:
<td align="center">
..............
gallery html code is here
</td>
Can you try this method and keep me posted?
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