I have the same vimrc file for both Windows and Ubuntu environments. It works fine on both platforms, except for one difference. The line:
nmap <C-[> <C-t>
is working fine on Windows, but on Ubuntu (14.04.2 64 bit) as soon as vim loads it puts me into replace mode and says "at bottom of tag stack", as if it's running the command immediately instead of just performing the mapping. I have other nmap lines before/after this one which don't cause any problems.
I'm on the latest vim on both platforms; on Ubuntu I'm using vim-gnome(huge build).