I understand your point of view. Honestly I am surprise by the Unicode API missing support for "wchar_t" very conventional for external usage.
Also, the described behavior is strange once a file is downloaded from Acrobat.com and not from local disk.
For instance the ASFileSysDisplayStringFromPath() returns different values:
"Kjøp og selg skiutstyr på Torge.pdf" - local file correct name returned by
"Kjøp og selg skiutstyr på Torge.pdf" - downloaded from Acrobat.com
This is not a correct behavior.
Update: If I'm thinking more... my customers don't know and don't use such Acrobat.com facility. Is it any registry setting that should allow automatically disabling of upload to Acrobat.com?