Global Mapper v25.0

How to set up raster exports to utilize multiple cores?

I am encountering some problems with using multi-core processing for exporting in tiled raster format. When trying to export from a  map catalog to a tiled GeoTIFF format (8-bit per band: 3-band)  using custom defined tile vectors there is mixed success in attaining multi-core processing, where the export progress bar contains '(x11)'. I have noticed that when I use custom tile boundaries multi-core works only when 'crop to selection' is not selected. When the tile boundaries are created within the tiling tab of the raster export menu the multi-core processing for export seems to be working. There seems to be quite a bit of variability in when multi-core exporting is activated depending on what settings and tiles are used.

What are the required raster export settings for multi-core processing to be used? Is there an option in a menu to always have multi-core processing switched on when doing raster exports?