Wyse 3040 ThinLinux Upgrade Security key failure

Trying to test different versions of ThinLinux on a 3040. I have a flash drive configured with the USB Imaging Tool, and both 2.1.0.01 and 1.0.7.1 on the drive. I have also updated the BIOS to the latest version 1.2.5. When I boot off the drive and attempt to install either image, I get a security key error. There appears to be little to no information available for this error.

I have a support ticket open with Dell, but wanted to see if anyone else had similar issues that could point me in the right direction.