Fluent v4 requires that your multiple block grid fit together into one large block. If Fidelity Pointwise cannot assemble your multiple block grid into a single block grid when exporting data for Fluent v4, you will receive an error message.
Fluent v4 does not allow poles (line singularities). Instead, use a small cylinder of finite radius. Fidelity Pointwise does not detect and warn of the existence of poles during export. Both 2D and 3D structured grids are supported.