1) Was something done to increase the morale or strength of the CW forces? Japanese forces were dropping like flies through the seven turns I played. Perhaps just bad luck, but it seemed odd.
2) Generally the same major problem with the Japanese AI - no air-ground support. After seven turns the AI had never provided air support for any attack along the roads.
Therefore no advance along the roads.
The Jap AI hit Shing Mun Redoubt every turn with land attacks, no air support, and got creamed every time. I suggest the AI have a low probability of attacking the redoubt region.