I have fixed the issue. Since you were putting the labels in their own group, none of them were assigned a value so they didn't display. When you use "show="incomplete"", the only thing necessary to show all labels is a single value for any of them. You may want to consider breaking them into two rows as the titles appear to be wrapping to the next line.
Instead of "BLADE" for blade damage type i wanted to add an image called File:SFIcon_Blade.png instead. So i used the <image> tag with <image source="SFIcon Blade.png"></image> but it won't show in the completed infobox sadly.
You would need to use site CSS with the selectors associated with portable infoboxes. In the example you provided, the labels are already centered. If you come across or already have an example where that is not the case, please link to it. As for centering the data, the CSS you should add is: