I'm not sure what you are trying to accomplish, since I don't worry about what layers are saved; I usually try to purge anything that isn't needed. However, if you use the routine:
(setq layer_find (tblnext "LAYER" 0))
(while (/= nil (setq layer_find (cdr (assoc 2 (tblnext "LAYER"

))))
(if ss_text (setq ss_text (append ss_text (list layer_find)))
(setq ss_text (list layer_find))))
You will create a list of the Layers that you can step through with the following and pull information from them just as you would wblocks or text or anything else:
(while (/= nil (cdr ss_text))
(setq layer_name (car ss_text))
Pull the information in this section until the following line becomes nil:
(setq ss_text (cdr ss_text)))
I hope this was of some help. I don't know the flag for a saved layer, but all of the data is pulled with the following syntax, if you key:
(setq layer_find (tblnext "LAYER" 0))
You get:
((0 . "LAYER"

(2 . "0"

(70 . 0) (62 . 7) (6 . "Continuous"

)
62 is color, 6 is linetype, and not all of the flags are shown in that list.