lichen , guttate psoriasis ,second opinion?

about 2 months ago mainly front trunk papular rash started slowly showing up
(- please see the situation now:
http://img839.imageshack.us/img839/8963/p1010266n.jpg)

that spread further and to forearms last month, maybe due to autoinoculation with
palms(which stayed clean)
However as I remember it did not start at waist area but with a kind of a burning
sensation and a ring made of papulas(bumps) above armpit
(please see http://img96.imageshack.us/img96/7295/0905101919.jpg)

Dermatologist said Lichen planus but neglected
almost no itch, clean legs&mouth and
the fact I had a beta hemolitic streptococcus skin infection; also
fresh papulas are flesh colored/later flatten out and get violet&red, and here and there you can notice smaller 'rings' made up of papulas (like the one at mid-left side of first pic)
Anyway I consider starting with oral erythromycin instead of prescribed oral glucocorticosteroid+gentamicin cream so I would like a second opinion possibly from:

guttate psoriais(as complication of maybe still existing
group-b-beta-hemolytic-streptococcus that was present),
Generalised granuloma annulare(but as previous it should not spread with autoinoculation,if it did take place)

and less likely
(Tinea corporis-unlikely because there are only few 'rings' and the edge is not sharp),
(Pityriasis rosea-guess not,although first manifestation looked could be considered 'herald patch',probably not- there are mostly bumps and not patches/macule),
(Candida ruled out-there is no sharp
border, no central clearing and no
satellite lesions),
(molluscum contagiosum unlikely because spots are tiny and not dimpled in the middle),(herpes no-no blisters),
('norwegian' scabies-should itch not only when new bumps are about to show up),