From Jan 2014 Geoplot 3 includes a free upgrade to Geoplot 4.0 when available
Geoplot Compatibility with Earlier Versions
Grid data, composite data and master grids (meshes) generated using earlier versions may be used directly with Geoplot 3.0. However, version 3.0 data is not backward compatible with version 1.2. Version 3.0 data may be read by version 2.0 but the resulting layout on the file information and history forms may not be as normal. Input templates generated with earlier versions are not compatible.
