Momentarily, the Chernarus stonewalls are used for Takistan and Zargabad:
I suspect this to be a bug. In earlier versions, the original Arrowhead stonewalls were used:
Their .p3ds seem to share filenames, but are located in different directories:
Takistan, Zargabad: "wall_stone.p3d","ca\structures_e\wall\wall_k\wall_stone.p3d"