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You have to be aware that there is a vertex numbering rule concerning the local coordinate system of the block.

It is described in the User Guide Chapter 5.3:
http://www.opencfd.co.uk/openfoam/do...#x25-1400005.3

Quote:

The local coordinate system is defined by the order in which the vertices are presented in the block definition according to:

the axis origin is the first entry in the block definition, vertex 0 in our example;
the http://www.opencfd.co.uk/openfoam/doc/gif/user461x.png direction is described by moving from vertex 0 to vertex 1;
the http://www.opencfd.co.uk/openfoam/doc/gif/user462x.png direction is described by moving from vertex 1 to vertex 2;
vertices 0, 1, 2, 3 define the plane http://www.opencfd.co.uk/openfoam/doc/gif/user463x.png;
vertex 4 is found by moving from vertex 0 in the http://www.opencfd.co.uk/openfoam/doc/gif/user464x.png direction;
vertices 5,6 and 7 are similarly found by moving in the http://www.opencfd.co.uk/openfoam/doc/gif/user465x.png direction from vertices 1,2 and 3 respectively.

Hope this helps!