Pointools / Vortex API - experiencing issues

We use the Pointools Vortex API v2.6.3.20 to support reading and writing the Bentley POD format.

We have recently received some customer reports that POD files generated contain bad coordinate values. We have been able to reproduce similar results using the PODWriter class in the API directly (not involving our products).

We have attached a modified version of the GeneratePOD.cpp example included with the PODWriter API, as well as a file generated by running this example.
- The example generates a grid of points where x is in the range [452500, 454727.5], y is in the range [6707500, 6709727.5], and z is in the range [250, 349].
- However, when reading the generated file back, several of the x and z coordinates have values like -10736965900 or 2.7200830220753216e+23.

Is this a known bug, or have we made an error in how we're using the API?

Any advice would be appreciated. Thanks