Post images not displaying proper.

I’m having some issues with the images in my posts. The “featured” images are fine and displaying properly but the “thumbnail” version of it on the front page is cut into what looks like a 3rd of the original image. When I read in the instructions this is what I find.

 

Categories

The categories impact directly on different divs of the site, so
choose wisely which categories you are going to add to the post.

Featured image

On the bottom right corner you will find a link called “Set
featured image”. This will allow you to upload and set a image
for the post. ( This works fine )

NEW in version 3.0: Add custom image for the post

We have added an option to add an custom image for the post to
make it look nicer on the site. Basically now you will have 2 images:
One that is the whole website and one for the post itself. To add a
custom image for the post please follow these steps:

• Upload your modified image in
  media

• Copy the direct link of the image

• In the post, scroll down to custom
  fields

• On the dropdown, select
  “inner-post-image”

• On the value field, paste your
  image link (please include http://)

• Click on Add custom field button on the left hand side and
  update the post

   

  I don’t have drop down anywhere I can see and nowhere in the post menu does it have “inner-post-image” . Please help this is my last step to making the site complete.