64 bit 11.01 Export 32-bit Geotiff Issues (Tile organized)
Exporting an elevation grid to a 32-bit Geotiff always creates a file that is unusable if the 'tile' organization is used. It seems to either create a file that has a few single rows of data at the cell size specified, followed by many rows empty, or creates a file that looks like its been corrupted and bears no resemblance to the input.
I took a look and you are right, the tiled elevation GeoTIFF was broken. I have placed a new build at http://www.globalmapper.com/global_mapper11.zip with this fixed for you to try. Simply download that file and extract the contents into your existing v11.xx installation folder to give it a try. If you are using the 64-bit v11 version there is a new build at http://www.globalmapper.com/global_mapper11_64bit.zip .
Let me know if I can be of further assistance.
Global Mapper Support