Make one of these your first flexbody line.
120,128,119, 0, 0, 0, 0, 0, 0, MaxDFlag.mesh
forset 119-126
120,128,119, 0, 0, 0, 0, 0, 0, MadusaFlag.mesh
forset 119-126
120,128,119, 0, 0, 0, 0, 0, 0, NEAFlag.mesh
forset 119-126
120,128,119, 0, 0, 0, 0, 0, 0, NNFlag.mesh
forset 119-126
120,128,119, 0, 0, 0, 0, 0, 0, SUD15Flag.mesh
forset 119-126
120,128,119, 0, 0, 0, 0, 0, 0, ZombieFlag2.mesh
forset 119-126