When I launch XTM it prints out a BIOS copyright message and then hangs. What have I done wrong?

Your DRIVEA.DSK diskette image does not contain a real DOS boot image. The most common mistake is to try to use a Windows 95 (or later) boot diskette for XTM. Windows 95 is a 32 bit operating system, and so is the Windows "MS-DOS mode" command prompt. XTM emulates a 16 bit Intel processor, and therefore cannot run Windows 95.