Q:

nmap key maps not working with Vim/Cscope

I'm using vim(7.3) with cscope in ubuntu. : cs find commands work fine, but I want to use some key bindings, so I download  cscope_maps.vim and install it according to the tutorial here.  However, no matter which place I put the vim file in, none of the key maps defined in the file work!  For example I got one of the mapping as :
nmap <C-\>s :cs find s <C-R>=expand("<cword>")<CR><CR>

When I moved the cursor on a c symbol and pressed [CTRL]+[\]+s, nothing happened! 
Does anyone know the reason and how to solve it? 
Thanks. 

A:

Try to isolate the problem.   First, while running vim, try something like
:nmap , :echo "hello"<CR>

and then type ,.   Assuming that works, try the key combination you actually want, instead of ,.   (When you write [CTRL]+[\]+s, you are using the CTRL and \ keys at the same time, right?)   If that works, then try the actual cscope command from the tutorial. 
Next, try adding a simple nmap command to your vimrc file.   Does that work? 
You should be able to load the script with
:source path/to/cscope_maps.vim

If that works, but simply dropping the file in your plugin directory did not, try
:set runtimepath? 

to see which directories are being searched for plugins, and read
:help load-plugins

(Step 4 under :help startup) for other reasons they might not be loaded.