Closing out this thread (I hope)
Butter's follow up was this morning. Doc said that Butter looks "remarkably better." He's filling out, hasn't done the 'lung suck-in' thing for at least a week, eating, pooping (Ooh, boy! Did he leave a biggin last night - which is currently undergoing exam, just to see if there's anything in there), and acting like a (getting) healthy snake should. Today's official weigh-in showed 449 grams! Happy me!
He has a small abraision down near his tail that I noticed when I first got him. No telling if a meal bit him or if he was housed with a lightbulb, but it wasn't very noticable even then. That's been getting better, too, and this next shed will probably get the last of the evidence off.
He's resting in a small 12 qt sterilite on my office bookshelf, staring at me through pink eyes. The highest I can get the office temp is 79.5 (so far) and I'm sweating. But that's okay.
Today's x-ray still clearly shows the dense spot on his lung, but everywhere else is much clearer. Could be scar tissue from something (maybe a previous infection) but since it is identical in shape, she concluded that it isn't viscous and probably will pose no problem. Obviously he eats, drinks and breathes just fine, whatever it is. His first x-ray (which I hadn't seen before today) also shows his GI tract literally filled with gas pockets. Poor guy looked like a cut-away drawing of a zeppelin or something. This was caused by his mouth breathing, and explains the gas-passing episodes that put my dog to shame a couple weeks ago. All clear now.
She concluded that he's "probably not contagious" anymore and said I can put him back in the rack with the anery babies. I think not! He's staying where he is, and I'm thinking about seeing if I can do a little re-arranging of furniture and maybe come up with a nice display viv for him. I forgot to ask, but I'm probably going to leave him on paper towels for a couple months more, too.
Thanks to everyone for your encouragement and concern. This hasn't been particularly easy and certainly not cheap. Your kind words have helped a lot. I felt responsible, at least to a degree, for his condition (stress of the move, handling far more than he was probably used to - he was just 'inventory' before after all, not finding out for sure what his previous diet and other living conditions were (substrate, size of housing, etc), not being prepared for a new snake in advance and struggling to get his temps right. So, in a way, I felt I owed him my best effort to get him well again. I've guaranteed that all I'll get for my birthday, father's day, anniversary, and probably next Christmas will be cards and a kiss, but it's been worth it.
Thus Endith the Butter Epic (knocking on particle board)...