1. Include entire gross disease at the time of presentation.
2. Margin of 2 cm respecting anatomical boundaries ok
3. Gorss nodes needs to be included
4. No need for prophylactic irrradiation

Constaints are not very well defined even for the adult patients - however as this study shows that underdosing carries a more severe risk of failure - I would concentrate more on getting the coverage and dose correct rather than thinking about normal organ constraints. Testicular shielding can be implemented but rest of the organs especially small bowel and rectum will get treated. Bladder I would not consider sparing at all.

Bones again are difficult point doses of 25 -35 Gy can be suggested as a cutoff but since you say the initial tumor was large it would be exceptionally difficult to achieve. As it is without surgery this patient is not receiving the optimal treatment. I found this reference where they modelled the effects of RT on bone growth
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T7X-4G0HV9J-3&_user=7895621&_coverDate=08%2F01%2F2005&_rdoc=1&_fmt=high&_orig=gateway&_origin=gateway&_sort=d&_docanchor=&view=c&_rerunOrigin=scholar.google&_acct=C000073114&_version=1&_urlVersion=0&_userid=7895621&md5=9b7dc2b6e489447aa54ff3ffb3437938&searchtype=a