By default, DynaTabs uses 4 thumbnail images. To add more, you go to these files (depending on which color scheme - light or dark - that you are using)
/components/com_virtuemart/themes/Dynatabs/templates/product_details/includes/js/css/dynatabs.tpl.css
or
/components/com_virtuemart/themes/Dynatabs/templates/product_details/includes/js/css/dynatabsDark.tpl.css
find the following line 105:
#showThumb0, #showThumb1, #showThumb2, #showThumb3 {
height:75px;
width:125px;
margin-left:2px;
margin-top:2px;
This line provides formatting for only 4 thumbnails. If you added more than that number, then there would be no CSS styling for them. To add more, add more thumbnail numbers like so:
#showThumb0, #showThumb1, #showThumb2, #showThumb3, #showThumb4, #showThumb5, #showThumb6 {
height:75px;
width:125px;
margin-left:2px;
margin-top:2px;
The above code change will render 6 thumbnails.
Now, the next problem is that the box in which the thumbnails is contained needs to be expanded. Find line 66:
#dynaTabsOtherImagesBox {
float:left;
width:200px;
height:350px;
background:none;
padding-right:4px;
padding-bottom:2px;
margin-right:0px;
}
Change the height here to match the height you need for the number of images that you want to have.
Each thumbnail has its own image styling. See this starting at line 26.
#dynaTabsActualImage1 {
position:relative;
background:none;
float:left;
margin-left:0px;
padding:0px;
border:thick;
border-color:#000;
}
You need to add a new section of the above code for each thumbnail you are adding.
Coding wise, you are done at this point.
You will probably want to use taller full size images to take up the extra space added by the new images.
.png){kind=small}
CiviCRM Extensions 
CiviCRM News Registration 