Image display is reflected by the CSS rules, and for this template "Strong Type by HTML5" that webkeytemplate.com is build upon there are three image classes.
This image uses class="image image-full" and it will take the whole width of the left column.
The image showing the image HTML attributes uses the class="image image-left" and is floating to the left.
Where do the classes come from ?
If there is a CSS selector in the webkeytemplate CSS database starting with IMG. it will be listed in this combobox.
If you do not use a class that will adjust the size of the image, it is possible to choose the create <height> and <width>. You can choose to adjust the size by changing the "Percent of original value".