I had to modify it a bit. The pound sign broke it, and I actually wanted >1 to get it to work the way I wanted.
Code:
program:
if and(
check_yes_no('#read', '', 1, ''),
field('#lastread'),
field('#percentread') >1
)
then
'Yes'
fi
Oddly enough, this resulted in another
small glitch that I reported on the bug tracker.