getting to a view directory

Start your linked URLs with "/", which will restart at your document root as far as the browser is concerned, and with your normal routing as far as CI is concerned.
In other words, "/sub_crud/form_reader/user_input".
UNLESS your document root is mapped to "sub_crud/..."? in which case the form URL might have to be "/form_reader/userinput".
OR you could link to "/configure/processtheform" (your main controller).

Hard to tell what your configuration is (folders, web server mapping, base_url), etc, hence the vague advice.