It features more props, new textures, enhanced skybox, sounds (which can be heard from the helicopter, the seagulls, and the raging sea) and of course, great effects (which can be customized by the quality slider).
The tunnels cannot be accessed at all, to force both players to face each other in the center, considering the thirty seconds time limit, if they could access the tunnel, it would likely end up in a stalemate.
As for the other way to access the tunnels and/or the vantage point, it's completely blocked by a large container, so there are no way whatsoever to access that place. Unlike the Bot TeamDeathMatch variant though, both doors on each side are still open.
This map has been slightly altered to accommodate with Bot TD mode in the Chinese version - much like Captain Mode, the alternate routes have been sealed off. It's likely done to simplify AI coding and not giving human players bigger advantage against Easy/Medium AI settings.
On Easy/Medium difficulties, players will spawn on the left side, right next to the left door, but on hard/very hard setting, players will spawn on the right side and must spend time moving toward the door to go out. This is done to remove respawn invincibility timer so players will have to face opponent bots without any protection.