I had to guess and backtrack, but can't do greens on iPad. Didn't need 'em.
Zemoxian, I am similar in the fact that i am using the xbox one to play this game. And like you it does not allow the use of greens. What i tend to do when the puzzle looks tricky is to write it all down and do it on paper.
I might try that. Almost done with 2006 except for a handful of hard and expert...
3 more 'perts' to get caught up. Better get some work done first.
Done with greens
Difficulty score 52. Got it pretty quick after filling in the greens.