We played tested this one. Worked pretty nice no big problems, and had fun there.
Don't use scenery and normal polys together, it's bothering if you are having a bridge of scenery and you can't shoot through it. I'm not saying that u should do "only player collide" polygon there (cos it's ur flagplace), I recommend deleting the bridge scenery and making polygon full visible.
Bottom route was out of game most of time. It should be smoothier/faster to get flag from bottom.