Cool. I found my error.
EDIT- Whoops! Saw you posted while I was typing. That's EXACTLY where my error was
So far, everything is working perfectly.
I'll let it run for a few days, letting some of my members test it out.
If anyone is interested, I'll post what I did.
Mind you, I am running 4Images intergrated with vBulletin, BUT none of those files changes were affected.
To try and make it clearer on what I wanted in my first post-
Upload a large image (primary) and it having it's thumbnail. That's 4Images typical. But I wanted one more field to upload zip files for download.
Now... given what I have done, super large images can be loaded as well and NOT be the one that loads up on the detail page!
Rather, this extra file is HIDDEN off the detail page UNTIL you click download.
Then it is this extra file that gets downloaded.
I know all of that could have been done from the Admin side of things already. But I want the MEMBERS to upload their own files.
What I have is a 3D modeling/CGI website, where meshes are made available to other members.
Generally, fols with this type of a site use paFileDB, which shows thumbs with the download file.
But paFileDB doesn't work with vBulletins member database.
4Images does with mods.
So what I did was effectively turn 4Images from a "gallery" to a Download Center