I've been trying all three (in this ''series''). Find them very hard to see. I managed this one, first. Was 10 off, 6 off, 4 off and 2 off, before that.
GREAT puzzle, IMO!
Very cool level! This was my favorite, maybe because I solved it first. Interesting series but the second and third felt much easier after tackling one.
EDIT: Hmm, not sure where this 68 is...
Wooow, great puzzle! I first had 120+ paths and couldn't see any better. Then I finally realized, there are more possibilities. Not easy for me to see, at all.