unetbootin doesn't generate a correct syslinux.cfg which can cause all sorts of problems as I found out. Here are the corrections you must make:
label ubnentry1
menu label ^Live (forensic mode)
kernel /ubnkern
append initrd=/live/initrd.img boot=live noconfig=sudo username=root hostname=kali noswap noautomount
should be
label ubnentry1
menu label ^Live (forensic mode)
kernel /live/vmlinuz
append initrd=/live/initrd.img boot=live noconfig=sudo username=root hostname=kali noswap noautomount
label ubnentry2
menu label ^Graphical install
kernel /ubnkern
append initrd=/install/initrd.gz video=vesa:ywrap,mtrr vga=788 -- quiet
should be
label ubnentry2
menu label ^Graphical install
kernel /install/gtk/vmlinuz
append initrd=/install/gtk/initrd.gz video=vesa:ywrap,mtrr vga=788 -- quiet
add
label ubnentry4
menu label ^Text install
kernel /install/vmlinuz
append initrd=/install/initrd.gz vga=788 -- quiet
I like the bleeding edge, but I don't like blood loss!