http://www.davidlynch.it/twin-peaks-the-secrets-of-the-room-above-the-convenience-store/

Long but amazing analysis of the convenience store. 

Notes:

From the script and deleted lines:

FIRST WOODSMAN
				(subtitled)
			We have descended from pure air.

			  MAN FROM ANOTHER PLACE
				(subtitled)
			Going up and down.  Intercourse between
			the two worlds.

Woodsmen talking about descending. 

Like the poem!

"This is the water and this is the well, drink full and descend, the horse is the white of the eyes and the dark within.”

Electricity..

The giant bell like objects in the giant/lady screen room and Naindo room. 

These are insulators!!! To defend from Bob like he green Formica ring!

"the famous green plastic laminate produced by Formica Corporation in its first form was used as an electrical insulator, and we know that electricity is a leitmotiv of Fire Walk with Me, and is related to these beings (perhaps moving through electricity) … A partial explanation might be this: the ring is designed to prevent possession by Bob (it is an electrical insulator). Laura, by wearing it, resists to possession (and in fact his “soul” is saved, as suggested by the final). "