Hi, not sure about your problem, because i know about this problem when you try to use BackBox with VMWare with only 512mb of RAM. After this, it's better to install english version 1st, not version with cyrillic letters (russian, serbian etc) :
/var/log/Xorg.2.log:
a few (WW) about ../X11/cyrillic, 100dpi, 75dpi, 100dpi, etc. does not exist.
And i don't see why you try to use 64bit version when 32bit version will support up to 4GB of RAM.
2nd error have something with xorg settings, but i don't see why, because you can see your boot screen.
I know that all this will not help you a lot, but try 32bit version, and say me if same problem comes back, then i will check documentations about errors like yours.
Good luck !