Okay, here's what I did:
1.) Edit the custom profile field so that its length can contain multiple file names (I like powers of 2 so I used 2^7 = 128)
2.) On my dev site, I went to a random user's profile in the User Manage within the AdminCP and entered the names of two image files I created for testing (separated by a comma):
Note: The add-on assumes the images have the extension "jpg" and are located off the root directory at "static/ranks". The images are stacked from top to bottom in the order in which they are entered into the profile field.
3.) Then I went to a thread where that user has posts, and made sure the images show up in the postbit:
So, please download the attached XML file and install it by following:
AdminCP ► Plugins & Products ► Manage Products ► Add/Import Product.
Click on "Choose File" and browse to the product xml file that you downloaded.
Click "Import"
Let me know about any changes you would like or if something doesn't work as expected.