>>662
??
単純化すれば、

(defvar navi2ch-window-stack nil)
(add-hook 'navi2ch-before-startup-hook
(lambda () (setq navi2ch-window-stack
(current-window-configuration))))
(defadvice navi2ch-exit (after window-pop activate)
(set-window-configuration navi2ch-window-stack))

この程度のもんだよ。