Oldtool
"Mr. BB1, for sure, still have the email where Weldwood CS said even the non-flammable needs all pilot flames extinguished. Surprised me, and made me then wonder if they say Low Odor, how low is low."

What else could they say?  They have liability issues.  
I've sprayed flammable contact cement with the space heater blowing.  I've sprayed and stuck I'm sure, well over a thousand sheets in my career.  No way I would ever worry about non flammable vapors.

Not trying to say anything bad about your decision,  just saying much to do about nothing in my opinion. 
The whole back could be done in 20 minutes with contact instead of days the way your doing it.  But I understand you have to do whatever makes you comfortable.

Figuring out how to do something you have never done is what makes a good challenge.