Homebrew PCBs

Haven't tried this, but would spraying the paper (any paper) with laundry
spray starch give a usable surface?  Since the iodine test indicates a
starch (dextrin?), just might be similar enough. And would prepasted
wallpaper, which you said has a dextrin content, work - printing on the
paste side?
Just a couple of late night thoughts while reading the e-mails.

Norm.