Suggestions for optimizing Argent Room Lenses?

My Merlin VSM-SE bBAM speakers are positioned according Merlin's guidelines at one end of a very large, rectangular space (14 ft. W x 30 plus ft. L x 8 ft. H).

Any suggestions for optimizing my 3 Argent Room Lenses, for this (obviously less than optimal) room, and for these speakers?

Any insights would be greatly appreciated!
A lot of experimenting is called for! But why not start with them 8" or so closer to the listener than the speakers are, and flanking the speakers (on the outside), and toed in a bit more than the speakers themselves are. You could also try to contact the Argent people, locate your speakers for them, and ask them were they'd start out the Lenses.

I found that moving mine as little as an inch made for a considerable deterioration in the sound. (This was one of those "cleaning lady" occurrences except that we don't run to cleaning ladies chez moi--it was my wife's doing.)
My suggestion is to flank the outside of each speaker with a lens, at a 45 degree angle. Place each lens about a foot outside of each speaker, and about a foot forward of each speaker.

Then take the last lens, and place it directly between the speakers, right where the center image would be.
I've tried placing the left and right outboard Room Lens as recommended by Argent, but to me this positioning doesn't seem to let the Merlin's "breathe" naturally (i.e. they seem to alter the soundstage the Merlins throw in a manner that just doesn't seem natural to me).

I am currently experimenting with corner-loading the Room Lenses in the left and right corners behind the speakers. Any tips from anyone else who has tried this configuration?
I have my lenses positioned as I described above, and my system throws a soundstage 4 feet wider than the lens positions. That's 4 feet wider on each side. I don't think that the lenses are limiting your soundstage.
ive had mine placed just as twl explains in his post,the center lens will control the depth of the soundstage,IF that gives your system too much of a wall of sound,try placing 2 lenses about a foot behind an imaginary line,behind & to the outside of the speakers,i found i got less digital glare from my system this way
Room lenses are not designed for use in the corners. If you use anything in the corners they should be bass traps. I have been using 3 lenses for a few years now in a similar fashion as described by Tom (TWL)and they make quite a difference with my Aerial 10Ts.