I'd be really interested in hearing how you got the swipe left/right commands to map to buffer management in MacVim.
if has("gui_macvim") "Use Experimental Renderer option must be enabled for transparencY
set transparency=15
set guifont=Monaco:h10
set noantialias " I like my Monaco this way ;D
" Swipe to move between bufers :D
map <SwipeLeft> :bprev<CR>
map <SwipeRight> :bnext<CR>
endif