Dragging files from Mail app or FTP the files show up on the wrong monitor

I have a Mac Mini (Intel) and I wiped my computer and started fresh with a clean install of Mountain Lion.

I have three monitors connected to my Mac Mini:

1. Connected via HDMI to DVI
2. Connected Mini Display Port to DVI
3. Connected USB to DVI

They are arranged via System Preferences so that the middle monitor is the main monitor and I can drag from center of middle to the left or right and hit the additional monitors.

Here's my issue:

On Lion I used to be able to have my Mail app open on the right monitor, drag a mail attachment out of the mail app and drop it on the middle monitor and it just appear there. Now when I do this the file appears on the right monitor behind the Mail app. I thought it was due to the location of the originating application - Mail app on right monitor file appears on right monitor, Mail app on middle monitor file appears on middle monitor. This is not the case. I opened my FTP application, CyberDuck, and it was located on the middle monitor, when I downloaded a file it appeared on the right monitor versus the middle monitor which is my primary Desktop.

Can anyone tell me what I'm doing wrong or if there is some way to resolve this? I'm at wits end.

Thank you kindly.

Shawn.