Pat,
i'm going to address your questions out of order, fastest first.  Soy formula
does not contain lactose, which is an important fuel for the brain (breaks
down at the exact rate that the brain needs energy) (See Lawrence) and is
important in the maturation of the gut (The Biological Specificity of Milk,
old LLL publication).  Mentioning this issue to my sister in law the Ross labs
rep caused her to freak out in denial.  Formula co's try to sell this lack of
lactose by citing transient lactose intolerance in bottle fed kids with severe
diarrhea.  The fact that their products caused the condition in the first
place never enters the discussion!
        HIV:  There was a hospital in the USSR which reused a syringe without
sterilization, infecting multiple infants with HIV.  About 7 infants passed
the virus to their bf mothers.  5 of these infants caused mom's nipples to
bleed, all 7 had oral candidiasis, a possible source of blood exposure.  This
was reported on OB/GYN update (cable tv) about 4-5 years ago, I have not seen
it in print.  So there is a theoretical risk to nursing an adopted baby.
        Adoptive nursing:  My moms with previous pregnancies, even if they
ended in spontaneous abortions had more success inducing lactation by pumping
that those with no previous conception.  I have found mammary hypoplasia to be
common in the latter case, the same mechanism that caused the infertility also
caused a marked reduction in glandular tissue.  All of this is perfectly
logical if one reviews the development of the mammary gland during fetal life,
adolescence and pregnancy.  I have also heard of women taking hormones to
induce this glandular development, but have no experience with this.
Personally, I would work with mom to clarify her goals:  bonding, immunologic
benefits, nutritional benefits, oral motor benefits?  Few of these are
dependant on a large milk supply.  The history and her goals will guide your
recommendations from there.  I hear on the grapevine here that the Lact-Aid
nursing trainer induces a larger milk supply than the SNS for adoptive moms
because of the active vs passive (gravity) feed of the devices.  I have
personally found pumping in advance to be most helpful for my moms with normal
breasts. Some of these issues were discussed before you came on board, you can
check the archives.
Good luck,
Catherine Watson Genna, IBCLC