Linking an image in Wygwam to a file using Assets (within Wygwam) isn't working

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Ok, so here's what's happening:
I upload an image within my Wygwam field by clicking the Image icon. This brings up the image properties where I can browse the server for an image using the Assets module. I have 3 directories set up in EE: Main in /var/www/html/uploads/, Files in /var/www/html/uploads/files/ and Images in /var/www/html/uploads/images/. I choose the images folder in Assets and upload my image. Everything's fine up to this point. Then, to link that image to a file, I click on the Link tab in the same Image Properties window. I click Browse Server and Assets comes up. Then, if I click on my files folder, no files show up (despite there being 3 files in that directory which can be seen by going to Modules > Assets). However, if I click on my images folder, all the images show up as they should. Problem is, I want to link my image to a file, not another image and no files are showing up.

Now, if I try to link some text to a file, it works perfectly. I click the Link button, browse the server using Assets and all the files in my files directory show up this time.

FYI: Since you can only choose 1 upload directory in the Wygwam editor configuration and I'd like to be able to use 2 (one for images and one for files), I set it to my "Main" upload directory so that I can access both the files and images directories in Assets within Wygwam. Is this a proper usage of these plugins or am I not supposed to do that?

I've tried using Firefox and Chrome, but the problem still happens in both. Any idea as to what it could be?

If you need any additional info, please let me know.

Thanks,
Eric