I want to use the right-arrow key to open a node in NERDtree. I see there is NERDTreeAddKeyMap, but I'm too much of a vimscript newb to know how to invoke it properly. I want right-arrow to invoke activateNode. I've done it by adding this line into NERD_tree.vim itself:
exec "nnoremap <silent> <buffer> <Right> :call <SID>activateNode(0)<cr>"
but I want to do it the right way in my .vimrc