Hello all,
This is much simpler than you would think. Whether you want to use an exsisting template or one of your, either way it is the same. The caveat here is that you are just trying to use normal (400x300 sized images).
Insert the tags you want except that I want you to only insert the tag "Description and Images" instead of any other number of tags you can insert for these. Save your template. Then when you are creating/editing a listing select the "change template" button. Find the templte you created by looking under the category "Custom", "Select" this template. In the following page,"Template Layout", look to the left hand column under the section "Customize Layout". Here you can choose the number of images to use, the grouping of those images(you will choose vertical for what you are after), then in the drop down box next to "Alignment" you will select "Right". This will give you the desired layout without having to do all the coding yourself. Let us know if you still have problems.