Here is my complete video walkthrough for Episode 1. The walkthrough is include all optional graffiti.
02:00 - Optional Graffiti #1 (Recreational Vandalism)
06:05 - Optional Graffiti #2 (I See U Saw)
14:25 - Optional Graffiti #3 (The Last Unicorn)
24:05 - Optional Graffiti #4 (Home Unimprovement)
32:18 - Optional Graffiti #5 (Rock Idol)
42:10 - Optional Graffiti #6 (Dramatis Personae)
45:35 - Optional Graffiti #7 (Mulligan Stew)
01:01:21 - Optional Graffiti #8 (Pioneer Spirit)
01:16:10 - Optional Graffiti #9 (Face Your Anger)
01:20:58 - Optional Graffiti #10 (Lucid Writing)