Simple problem: when inside a block with one or more nested blocks, exporting one of the nested blocks using the file -> export selected command does not work as expected. The resulting file only has the block definition, but not the block instance inside. Opening the new file and copy+pasting the nested block works fine.
Testfile: nestedBlockExportProblem.3dm (37.2 KB)
Try to export the “ExportMe” block and see for yourself. r6 sr24 on win10.