Hi, can someone please advise on this? It seems like a bug, or "inconsistent/undesirable behaviour" at least 
If I have a compressed drive and an uncompressed drive, I'd expect that any file that I copy between the two locations would inherit the parent folder's compression state, regardless of the "preserve attributes of copied files" setting, as the attribute inherited from the parent would take precedence over this setting. This is how Windows behaves, and as far as I can tell, how Directory Opus behaves too, except that Dopus only works this way in regard to files.
Where it runs into trouble is when copying a folder from a compressed location to an uncompressed location - the folder copy remains compressed in the destination when it should inherit the destination parent folder's compression attribute. Strangely the reverse is not true: copying a folder from a non-compressed location to a compressed location results in NTFS compression being enabled on the copied folder, as one would expect.
This makes a for an unwanted mix of compressed and uncompressed files when I copy documents between my laptop (compressed) and desktop (compressed).