[xwiki-users] Users can't upload Images?

I've been the administrator of my team's Xwiki for several years now. I recently upgraded to Xwiki Enterprise 2.7.1.34853 from Xwiki Enterprise 2.4. Everything seems to work great for me, but my team members can't upload images to pages and they are occasionally seeing their page text content disappear when they go back and forth between "WYSIWYG" and "Source" while editing. In the WYSIWYG editor, they click on "Image" -> "Insert Image...", but instead of seeing the message: "Select an image to insert from the list below, by clicking it, and then advance to the next step, or double click an item to automatically select it and advance to the next step." along with the thumbnails or the box to upload a new image, they see a red circle with an "!" and message saying "There was an error loading the data" We are all using Firefox, but I'm running Ubuntu Lucid and they are running Windows. The server is also running Ubuntu Lucid. I'm using MySQL as the database. Strangely, they didn't see any problems with Internet Explorer (i think ver 8) During this upgrade, I went straight from 2.4 to 2.7. I didn't see anything that indicated I needed upgrade incrementally. I also noticed that I should be using InnoDB tables instead of MyISAM. I used "ALTER TABLE.." commands to change the db tables to InnoDB by hand. When I installed the WAR and modified the xwiki.cfg, I made sure the migration flag was set to true. The other change that I made was that I enabled our authentication to use LDAP, but my users weren't having problems with their LDAP accounts. They were using their old standard xwiki user accounts they had created several years ago. When they did login with their LDAP accounts, they experienced the same problems. I originally thought this could have something to do with User rights, but I created a test user with the same privileges as my users and it worked just fine. The good news is that it appears that we found a workaround with Internet Explorer, but has anyone ever heard of this problem? Or know how to fix it in Firefox? The other good news is that I have nightly backups of my database and I also have the older installation of xwiki backed up. So, I could always roll things back if need be, but I would hate to do that. Any help would be appreciated. Thanks, travis riggs