Ahhh, I thought that you want to change [b]only[/b] css and js paths. But there is the $default_theme_path that exist in Grocery, and this is apply many other css and js files to work. Look at the files in the ./assets/grocery_crud/themes/flexigrid/views/ for example.
In this case, if you want to change all paths, you have to write another one function set_default_theme_path:
public function set_default_theme_path($path)
{
$this->default_theme_path = $path;
}
and of cause add to the controller
$crud->set_default_theme_path('your/new/theme/path');
Probably you want to change other paths to texteditor and language files in your project. Look at the Grocery CRUD library near the line #2695.
P.S. When I tell about trailing slashes I meant the trailing slashes not after SHARED_DIR, but after "plugins[color=#ff0000][b]/[/b][/color]"
By the way for what do you change the paths? I'm just interesting.