There are a few areas off line that you just can't get to unless you use sticker slap or Wall ride OB2 to get to it. You must follow the guide lines of the classic OB2. But with small twists for example. When you want to get on the grassy area http://bgoatclan.com/glitchdatabase/index.php?showtopic=2514 off line by sticker slapping the white building right above the ground. Then in mid sticker slap pause and set custom. After that goto custom while pressing r1 and l1 to get off board
keep doing this until you ob2. This can also be done with wall rides if u set cust during wall ride above an ob2