Loading tiffs with Dropbox Plugin

I am suddenly having problems loading tiffs into Omeka. (I’m using the Dropbox Plugin and then manually adding the files to each item.) My IT guy says that we have no restrictions on file size, so I’m wondering if it might be a problem with the Dropbox Plugin. Any ideas?

Let me clarify: Instead of getting a thumbnail which links to a detail page on the image, I get the filename and a link that opens up the image outside of Omeka.

I don’t think Dropbox is likely the issue here.

But, if you suspect Dropbox, have you tried just uploading one of the images through the normal upload interface to see if the same problem happens?