Insert Image Popup fails to fully load

[scifi-meshes]

After pounding my head I have determined that this ERROR is because my work computer is behind a FIREWALL which apparently prevents certain things from happening. I view this on another machine not behind the firewall and everything shows up just fine.. Go figure.. hours wasted.

[scifi-meshes]

The Problem: When anyone uses the quick-reply to insert an image, the popup that usually appears never fully loads such that someone can upload/attach an image.

The History: I am running MARCO1 Advanced Quick Reply - Advanced Quick Edit - With Smiles!! found here: http://www.vbulletin.org/forum/showthread.php?t=232730. I have uninstalled, then reinstalled this hack to see if that was causing the problem. It was not as the problem exists with the mod installed and removed.

The Setup: I have the assets manager turned off. Attachments are held on the server in a folder outside the database.

The things I have tried: I have reverted just about every template, save the ads templates. So all of my templates are as they come from Vbulletin.com. I have attempted to find the STYLEVARs that could be effecting this popup window, however I can find nothing wrong. It's my understanding this popup is controled by the "BLOCK" stylevars. ALSO: The popup does NOT load from vbulletin's 4.0 DEFAULT template. So I do not believe this is style specific.

UPDATE: When you click on the VIDEO icon the popup to insert video comes up immediately.

Please see that attached image. If you can point me towards a possible solution. I would greatly appreciate your help as I have exhausted my possible solutions.