I guess Bud was hoping (as was I) that someone knew of some freeware available on a site somewhere, that would allow a URL to be included in a post, with the result that the picture would simply be displayed automatically within the post.
I am a frequent poster to the U.S. Chess forums (
http://main.uschess.org/forums/) which also uses phpBB. Somebody over there pointed me to a site which would allow this exact thing, with chess diagrams.
Unfortunately, even if somebody created a similar tool for Sudoku, it probably wouldn't work with phpBB2, the version used here. U.S. Chess converted to phpBB3 a while ago.
Bill Smythe