File association on macOS version can't deal with special characters in file name

[yqxq]

I tried to open Androïden Nim.cas, and then it says no cassette and makes a 0kb file with the name Androi?den Nim.cas

[dionoid]

Opening Androïden Nim.cas on macOS via the M2000 UI/menu works fine, but using file-type association (i.e., double-clicking a .cas file to automatically open it in M2000) fails on macOS when the filename contains diacritics.
On Windows and Linux this isn't an issue.