NerdTree Janus Fix

.gvimrc

autocmd WinEnter * call s:CloseIfOnlyNerdTreeLeft()

" Close all open buffers on entering a window if the only
" buffer that's left is the NERDTree buffer
function s:CloseIfOnlyNerdTreeLeft()
  if exists("t:NERDTreeBufName")
    if bufwinnr(t:NERDTreeBufName) != -1
      if winnr("$") == 1
        q
      endif
    endif
  endif
endfunction

.gvimrc.local

function s:CloseIfOnlyNerdTreeLeft()
" Override function in Janus
endfunction

.vimrc.local

nmap <C-B> <Plug>Kwbd

kwbd.vim

" http://vim.wikia.com/wiki/Deleting_a_buffer_without_closing_the_window
" delete the buffer; keep windows; create a scratch buffer if no buffers left
function s:Kwbd(kwbdStage)
  if exists("t:NERDTreeBufName")
    if bufwinnr(t:NERDTreeBufName) == winnr()
      return
    endif
  endif
  if(a:kwbdStage == 1)
    if(!buflisted(winbufnr(0)))
      bd!
      return
    endif
    let s:kwbdBufNum = bufnr("%")
    let s:kwbdWinNum = winnr()
    windo call s:Kwbd(2)
    execute s:kwbdWinNum . 'wincmd w'
    let s:buflistedLeft = 0
    let s:bufFinalJump = 0
    let l:nBufs = bufnr("$")
    let l:i = 1
    while(l:i <= l:nBufs)
      if(l:i != s:kwbdBufNum)
        if(buflisted(l:i))
          let s:buflistedLeft = s:buflistedLeft + 1
        else
          if(bufexists(l:i) && !strlen(bufname(l:i)) && !s:bufFinalJump)
            let s:bufFinalJump = l:i
          endif
        endif
      endif
      let l:i = l:i + 1
    endwhile
    if(!s:buflistedLeft)
      if(s:bufFinalJump)
        windo if(buflisted(winbufnr(0))) | execute "b! " . s:bufFinalJump | endif
    else
      enew
      let l:newBuf = bufnr("%")
      windo if(buflisted(winbufnr(0))) | execute "b! " . l:newBuf | endif
  endif
  execute s:kwbdWinNum . 'wincmd w'
endif
if(buflisted(s:kwbdBufNum) || s:kwbdBufNum == bufnr("%"))
  execute "bd! " . s:kwbdBufNum
endif
if(!s:buflistedLeft)
  set buflisted
  set bufhidden=delete
  set buftype=nofile
  setlocal noswapfile
endif
  else
    if(bufnr("%") == s:kwbdBufNum)
      let prevbufvar = bufnr("#")
      if(prevbufvar > 0 && buflisted(prevbufvar) && prevbufvar != s:kwbdBufNum)
        b #
      else
        bn
      endif
    endif
  endif
endfunction

command! Kwbd call <SID>Kwbd(1)
nnoremap <silent> <Plug>Kwbd :<C-u>Kwbd<CR>

" Create a mapping (e.g. in your .vimrc) like this:
" nmap <C-W>! <Plug>Kwbd