Instead of using the install icon on the desktop, try starting the installer from a terminal (Konsole) and when it hangs, if it does, take a note of the error/s and post them back for others to look at. They may indicate what the problem is.
Can't use a terminal on a program that has my computer locked. Can't even move the mouse.
That does not make any sense to me.
If it is not locked sufficiently to click on the launch icon then it is not locked sufficiently to launch a terminal and type in a command ......