@Ghot
So I've been able to come a little further with it. Yes, you were right about turning "Secure Boot" off.
Here's an
imgur link which has a series of pictures of my screen as I move-through the boot-up sequence of the USB-Drive. Sorry that the images are not very clear, if you need me to I can re-format them to make them clearer and then re-post them.
Picture 1 shows my "Boot Configuration" screen in my BIOS. Note that I turned "Secure Boot" off after taking that picture.
Picture 3 (it should be the second in order, I know, sorry) shows the menu-screen I'm greeted with after booting up the USB-Drive.
Picture 2 (again, this should be the third in order, sorry) is what is presented to me if I choose the rightmost option of the menu seen in picture 3. The title of the option is something like "SeaGate Command-Line Tools".
Picures 4-7 show the sequence it presents to me if I choose either the leftmost option or the central option of the menu seen in picture 3--both of those two options seem to run exactly the same sequence. The title of the leftmost option is "Boot SeaTools X", and I think the title of the central option is just "Boot SeaTools". Pressing enter at picture 7 just adds a new line with the current time and date.
Picture 8 is what it shows when I use "Ctrl+Alt+Del" to shut the PC down when at the screen of picture 7.