Got an email from the designer of this theme.
Here is a place to start:
Open dark.css in the editor or stylesheet.css if you are using the light version. Find:
.left img {
width: 500px;
width: expression(this.width > 500 ? 500: true);
height: auto;
}
.left img effects how the style is applied to Nextgen Gallery thumnail images. So adjust this until it looks right. I just made the width: auto; and deleted the next width statement.