I have a file with these hashes:

crc32: ffffffff md5: ad6fb7d18d74505cdfffa7d16bee51fc sha1: 20b37e3c8144a9fba22696ee9d2345379f091820

In Dir2dat mode (dat creation) CrlMame give to me thit result:

game (
name "xxxxx"
description "xxxxx"
rom ( name 1.iso size 546971648 flags nodump )
)

ClrMame version is 3.106c