I've almost run out of ideas, and so i'll ask a question:
how many letters (or numbers) do we have to pick out of every glyph? I'll say two (one for the user, the other for the pass). Since things must be made easy, I'll say so:

eliminate from G2 67, 3 and 70 (67 + 3 = 70), and 13, 25 and 38 (for the same reason). Thus, we are left with only two numbers (as usual, mine is a self satisfying prophecy) 11 and 48, which I propose as solutions to G2. In case letters are needed,

11 = J

48 = 22 mod 26 = V