In the past (before version 0.72) the DRO had header with low part of version equal 1 and high version greater than zero.
Here is a file with this version number. I have implemented in my player versions 0.1, 2.0 and this one but I have one problem.

The samurai.dro (after addition setting of register 0x01 to 0x20) is played correctly but the dune1.dro has one instrument with wrong timbre. I don't know how means 8th and 9th byte of this format. Currently I ignore these bytes.

None player supports this format thus I cannot debug it.

Can you please describe changes between this format and DRO version 0.1 (used in DOSBOX before 0.72)?