I'm using MM 2018 v. 18.1.154 on Windows 7. I have attempted to export my map at 8000 x 6000 and 12000 x 9000 in BMP and PNG. Every time I do so, the image file is empty. I have been successful at 6000 x 4500 resolution but the map is unreadable at that resolution. MM's online documentation tells me that there is no maximum resolution for an exported image file. Anyone have any idea what's going on?