Hi Rich,
Here might be a solution if you are willing to try it. Try and reflash the BIOS with either the same BIOS firmware version or the latest (your call). This is how you might do it. Found this quote whilst trawling for a solution, it came from this link - there are a few options discussed on this page. They were talking about how a firmware update stopped their T100 (T100TA) from booting and they had no access. The problem firmware was withdrawn so hopefully only good ones are left on the Asus site
http://answers.microsoft.com/en-us/windows/forum/windows8_1-performance/asus-t100-transformer-tablet-running-windows-81/24d3e618-be61-49a8-89c7-831db8bf902e?page=3&auth=1
"......flash the BIOS without having the computer boot by pressing the Power and Esc buttons at the same time. He could then indicate that the new BIOS was on a flash drive connected to the USB input".
If it succeeds it may (stress only may) allow you to change options in BIOS