Start bash shell (cygwin) with correct path without changing directory

I haven't toyed with UNC paths, but in general you have to use forward slashes instead of backslashes I believe. For regular drives, you can use /cygdrive/c for example to access the C drive.

In a batch file, to open the shell to the root of C: you could use:

c:\cygwin\bin\bash.exe --login -i -c 'cd "/cygdrive/c";bash'

You may also be interested in chere a context menu entry for Open bash here:

You could try a bash function to pass the arguments before the ampersand:

np ()
{
    /cygdrive/c/Program\ Files/Notepad++/notepad++.exe $* &
}

BUT the bigger issue may be the whole idea of not waiting until Notepad++ exits. Shell commands which use $EDITOR typically are designed to wait until the editor sends back an indication that the editing has completed. This usually means that the editor has exited (e.g. with vi or nano).

Emacs has a way to set your EDITOR to emacsclient and then when you're done editing, you hit a magical keystroke (C-x #) to indicate that editing is complete. If Notepad++ had something similar for cygwin users, I can see how this would work.

Another alternative is to use plain, boring, simple Notepad as your EDITOR and reserve Notepad++ for heavy use (I got the idea from this blog post)